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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                    Form 10-K

Annual report pursuant to Section 13 or 15(d) of the Securities Exchange Act of
1934

FOR THE FISCAL YEAR ENDED OCTOBER 31, 2003

                        COMMISSION FILE NUMBER 000-21109

                                CUNO INCORPORATED
                              ---------------------
             (Exact name of registrant as specified in its charter)

           Delaware                                              06-1159240
-------------------------------                              -------------------
(State or other jurisdiction of                               (I.R.S. Employer
 incorporation or organization)                              Identification No.)

400 Research Parkway, Meriden, Connecticut                              06450
------------------------------------------                            ----------
(Address of principal executive offices)                              (Zip Code)

                                 (203) 237-5541
                                 --------------
              (Registrant's telephone number, including area code)

SECURITIES REGISTERED PURSUANT TO SECTION 12(B) OF THE ACT:
              NONE

SECURITIES REGISTERED PURSUANT TO SECTION 12(G) OF THE ACT:
         COMMON STOCK, PAR VALUE $.001 PER SHARE
                  (Title of class)

         Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to the
filing requirements for at least the past 90 days. Yes [X] No [ ]

         Indicate by check mark if disclosure of delinquent filers pursuant to
Item 405 of Regulation S-K is not contained herein, and will not be contained,
to the best of registrant's knowledge, in definitive proxy or information
statements incorporated by reference in Part III of this Form 10-K or any
amendment to this Form 10-K. [X]

         Indicate with a check mark whether the registrant is an accelerated
filer (as defined in Rule 12b-2 of the Exchange Act). Yes [X] No [ ]

         As of November 28, 2003, approximately 16,870,791 common shares were
outstanding, and the aggregate market value of the common shares (based upon the
last price on that date) was approximately $718.8 Million.

                       DOCUMENTS INCORPORATED BY REFERENCE

         Portions of the Proxy Statement for the 2004 Annual Meeting of
Shareholders are incorporated by reference into Part II, Part III and Part IV of
this report to the extent described herein.

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                                     Part I

ITEM 1. BUSINESS

(a) General development of business:

         CUNO Incorporated ("CUNO" the "Company", or "we") is a world leader in
the designing, manufacturing and marketing of a comprehensive line of filtration
products for the separation, clarification and purification of liquids and
gases. Our products, which include proprietary depth filters and semi-permeable
membrane filters, are used in the potable water, fluid processing, and
healthcare markets. These products, most of which are disposable, effectively
remove contaminants that range in size from molecules to sand particles. Our
sales are balanced between domestic (approximately 55%) and international
markets (approximately 45%).

         Our objective is to provide high value-added products and premium
customer service. Our proprietary manufacturing processes result in products
with features that lower customers' operating expenses and improve the quality
of customers' end products. As part of our commitment to customer service, we
designate our own scientists, each of whom possess particular industry
expertise, to collaborate with customers on specific projects to insure
satisfaction with its products and to create new products.

         Our success is partially dependent on the development and
implementation of the following initiatives, which are key elements of our
ongoing growth strategy: (i) develop new products for specific markets, (ii)
decrease product development cycle times, (iii) develop pre/final filter
systems, (iv) increase customer satisfaction, (v) improve operating
efficiencies, and (vi) pursue selective acquisitions.

(b)      Financial information about industry segments:

         The Company is divided into five geographic operating segments, each of
which has general operating autonomy over its products and local operations.
These operating segments are as follows: North America, Europe, Japan,
Asia/Pacific, and Latin America. See Note 9 - Segment Financial Data on pages
33-35 of the 2003 Annual Report to Stockholders which is incorporated herein by
reference.

(c)      Narrative description of business:

OVERVIEW: Filtration is the process of separating particles of various sizes
from liquids or gases. The mechanics of filtration range from the removal of
coarse contaminants, most often particulates, as large as 200 microns such as
sand and sediment, to the elimination of bacteria and viruses at less than .01
micron (human hair is typically 20 microns in diameter). A filtration device
consists of a plastic or metal housing and a filtration medium. Filtration
media, which can be manufactured out of a variety of substances, act as the
separator or barrier in the filtration process.

         Filtration media include microporous membranes, glass, synthetic and
cellulosic fibers, porous metals and ceramics. Microporous membranes are thin,
film-like materials with millions of uniform microscopic holes. Membranes are
the most widely used filtration media because they remove specifically-sized
particles and can be configured into a variety of shapes and sizes. Each of
CUNO's five operating segments manufacture and sell products into the potable
water, fluid processing, and healthcare markets.

OPERATING SEGMENTS: We serve three primary markets through a geographical
operating structure. Each of our five operating segments (North America, Europe,
Japan, Asia/Pacific, and Latin America ) manufacture and sell products into the
Potable Water, Fluid Processing, and Healthcare markets. These markets represent
the end markets in which the customers reside. Since the nature and attributes
of the markets vary widely by geographic region, to best address these markets
we have established a management structure based upon geography. The management
for each of the geographic regions operate independent sales and manufacturing
organizations that function within an overall

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corporate framework of strategic initiatives and performance targets. The
majority of these initiatives and targets are established to best address the
three major markets and to achieve the financial objectives of the business.
Further detail on our three major markets follows:

         Potable Water: The potable water market includes residential,
commercial, and food service customers. According to industry data, it is
estimated that one billion people in the world do not have safe drinking water.
Demand is driven both by consumers' desire to improve the taste and quality of
their drinking water and by the expanded concern of regulatory agencies. North
American sales have increased sharply since 1999 due primarily to exceptional
growth in new appliance filters for the OEM market and, to a lessor extent, as a
result of the successful assimilation of certain small acquisitions. Growth
potential appears especially strong in Asia/Pacific and Latin American countries
where the quality of drinking water has been found to be severely deficient in
several regions. Water safety concerns have driven the growth of the consumer
bottled water market to over $2 billion in the United States, as well as the
growth in the water filtration market.

         The food service industry has an increasing need for consistent global
product quality. Food service includes water used for fountain beverages, steam
ovens, coffee and tea (i.e. "recipe quality water"). Specifically, restaurants
have become increasingly aware of the need for water filtration to control the
taste and quality of the water used in their businesses. Worldwide sales to the
potable water market totaled $132,938,000, $119,456,000 and $107,263,000 during
the years ended October 31, 2003, 2002, and 2001, respectively.

         Fluid Processing: Major customers in the fluid processing market
include chemical, petrochemical and oil and gas processors, manufacturers of
paints and resins, producers of electronics and semi-conductors, and power
generation facilities. As sophisticated manufacturing processes increase and as
the adoption of practices focused on quality increase, we believe the demand for
filtration products will also increase. In part, this trend is driven by the
enhanced ability to detect contaminants in process streams. As automation
increases, focus on quality control increases, and as the ability to detect
contaminants progresses, fluid filtration will play a greater role in the
manufacturing process.

         A significant segment of our fluid processing market is electronics
manufacturing. Ultra pure water is used to rinse the components during
manufacturing in order to ensure that the product is particle free with no
residual contamination. The industry uses corrosive, high purity chemicals and
gases for the manufacture of computer chips, hard disks, video terminals and
other components. All of the chemicals and gases used are processed through very
fine filtration systems. The strengthening demand for electronic products and
oil and gas products has helped recent sales growth, and certain new products
are expected to stimulate growth in the future. Sales to the fluid processing
market totaled $74,626,000, $68,714,000 and $71,898,000 during the years ended
October 31 2003, 2002, and 2001, respectively.

Healthcare: The healthcare market is experiencing rapid growth as a result of
the intensive research efforts to find cures for diseases, the increasing use of
rapid and simpler diagnostic tests to help reduce healthcare costs, the trend
toward finer and more cost-efficient filtration and increased governmental
regulation. When harmful elements are identified, they are often regulated or
new medical standards of care are implemented to decrease or eliminate contact.
In many cases, fluid filtration can play a key role in eliminating contact with
many harmful elements. Price is not the primary factor in the customers'
filtration decision process, but rather the performance and reliability of the
product.

         Our healthcare market customers include pharmaceutical and
biotechnology companies that require cost-efficient filtration and high levels
of purity for production of sterile, contaminate free drugs, as well as
producers of diagnostic test kits which require highly efficacious membranes. In
addition, applications include the production of bacteria-free water and food
and beverage products. Sales to the healthcare market totaled $80,667,000,
$70,031,000 and $65,288,000 during the years ended October 31 2003, 2002, and
2001, respectively.

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GROWTH STRATEGY: Our goals are to grow at a rate higher than the general
filtration market, expand our market share and to increase our operating margins
and profitability. Key elements of our growth strategy include:

         Develop New Products for Specific Markets. We have initiated a strategy
to develop high value-added products for specific markets. Historically, we
offered non-differentiated products and often competed solely on price. To gain
a better understanding of specific markets and guide new product development, we
introduced Scientific Application Support Services ("S.A.S.S."). S.A.S.S. uses
scientists with post-graduate degrees who are experts in the specific industry
they serve. They collaborate with customers who are developing and implementing
new processes or products that have specific filtration requirements. Often
these relationships lead to the development of new market-specific products.

         Decrease Product Development Cycle Times. We have decreased our product
development cycle times to approximately 18 to 24 months. This improvement has
occurred through increased market focus, collaboration with leading-edge
customers through S.A.S.S. teams and the formation of cross-functional product
launch teams. We believe we can continue to shorten product development cycle
times through these same methods.

         Develop Pre/Final Filter Systems. Many filtration systems have one or
more pre-filters to remove large contaminants from the liquid or gas before it
passes through the final filter, prolonging the life of the more expensive final
filter. When these filters are designed together in a system, the performance of
the system is enhanced. We have a leading pre-filter market position and are
expanding the number of final filters we offer. This allows the Company to
provide its customers with a total filtration solution from one vendor.

         Increased Customer Focus. We have traditionally sold to distributors,
who in turn sell to the end user. Our current goal is to provide unmatched
customer service to our end-user customers, while providing resources to our
distributors. In many cases the customer is unable to define its filtration
needs accurately and seeks outside resources to identify and choose the best
filtration alternative. Our S.A.S.S. professionals meet this need. Management
has been training and focusing distributors on specific market segments and
providing additional training, sales, and marketing support. This enables
distributors to provide customers with superior industry expertise and
company-specific product knowledge.

         Improve Operating Efficiencies. We believe we can improve operating
efficiencies by offering higher margin new products and implementing cost
controls, supply chain management, productivity gains, profit-based compensation
programs and outsourcing production of certain processes. We have initiated a
capital investment program designed to (i) integrate cell-based manufacturing,
(ii) provide higher yields from raw materials, (iii) improve inventory
management, (iv) lower labor costs, (v) reduce manufacturing cycle times, and
(vi) reduce scrap rates.

         Pursue Selective Acquisitions. We review opportunities to acquire
high-quality companies which will allow us to expand into new geographic
markets, add new customers, provide new products, manufacturing and service
capabilities or increase our penetration with existing customers.

In fiscal 2002, we completed a product line acquisition in Australia and a
distributor acquisition in Europe for total consideration of $700,000. The
amount of goodwill and other intangibles recorded in connection with these
acquisitions amounted to $250,000 and $244,000, respectively.

In the second quarter of fiscal 2001, we completed two acquisitions - a product
line in Australia and a distributor in Europe -- for a total cost of $4.5
million. These acquisitions did not have a material effect on the our historical
financial statements or pro forma operating results

PRODUCTS: We manufacture a full range of products by offering our customers
solutions to a wide range of filtration requirements. Many of the products
manufactured by us use electrokinetic adsorption, a proprietary chemical process
we developed which alters both membrane and depth filter media surfaces.
Electrokinetic adsorption uses molecular

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charges on dissolved ions to bind finer contaminants to the filter surface. This
attribute significantly enhances filtration efficiency by removing contaminants
smaller than the micron rating of the filter. We typically group our products
into the following categories:

Membranes: The typical polymer and nylon membranes that we produce resembles
plastic films except for the molecular size pores that are engineered into the
surface and depth of the membrane. By varying pore size and altering the
physical or chemical properties of the membrane, the quantity and type of
substances which can pass through the membrane can be regulated with absolute
certainty. We manufacture "absolute rated" products where no particle above a
certain size can pass through the membrane. In many applications, these
membranes can be integrity tested to ensure specific performance both at the
beginning and end of a particular process. A membrane can be employed in a
variety of configurations, including flat sheets, discs and cartridges that
contain high surface area and pleated membrane media.

         Uses of membranes include water purification for electronics and
applications in semiconductor manufacturing, pharmaceutical, biotechnology and
other applications, as well as residential use for drinking water.

         Our products include those sold under the following labels: Zetapor(R),
Microfluor(R), PolyPro(R), Zetabind(R), Electropor(R)II, BevASSURE(R),
MaxMedia(TM), Synchro(TM), Acro(TM), AC/PH Lithowater(R), LifeASSURE(R),
PhotoSHIELD(TM), OPTIMA(TM), SterASSURE(TM) and Novylon(R).

Depth Filters: Our disposable depth filters are constructed from a matrix or
formation of very fine and micro-fine fibers such as polypropylene, cotton,
polyester, glass fiber, acrylic, rayon, polymer, carbon and other materials. The
fibre matrix is then processed into a rigid filter media using techniques such
as thermal bonding, resin bonding, pleating or winding. Our technology has a
strong emphasis on graded density attributes and electrokinetic adsorption.
Graded density depth technology allows filter media to be manufactured with very
open porous outer layers, progressively becoming smaller in the size of the
pores or void volume through the depth of the filter media. Graded density
construction extends filter life in many applications and reduces pressure loss
across the filtration process thereby reducing energy costs. The structure of
graded density filter media allows particles to be trapped throughout the depth
of the cartridge which minimizes surface binding, allows for high contaminant
capacity and lower pressure drops than solely trapping particles on the surface
of the media.

         We manufacture depth filters in a wide variety of cartridge and pore
sizes with "absolute" particulate ratings. The filter cartridges are used in
filter housings that can be manufactured in a broad range of metals or plastics
to suit particular customer specifications. Filter housings are designed for a
wide range of temperatures and pressures.

         Our depth filter products include those sold under the following
labels: Zeta Plus(R), Betafine(R), Micro-Klean(R) III, Beta-Klean(R),
Betapure(R), PolyNet(R), BioCap(R), Micro-Wynd(R) II, Econo-Klean(R),
Virosorb(R), Petro-Klean(R), Delipid(R), , Zetacarbon(R), and MPF(TM).

Cleanable Filters and Systems: We design and manufacture an extensive range of
self-cleaning disc filters, backwash strainers and recleanable metal filters.
The self-cleaning disc filters and backwash strainers can be electrically or
mechanically operated with automatic controls to provide for specific
requirements in process applications. The recleanable metal filter elements are
constructed of sintered porous stainless steel or metal screens in tubular and
pleated construction. The recleanable elements can be cleaned in place in a
filter housing or removed for mechanical, ultrasonic or chemical cleaning.

         Our cleanable filters and system products include those sold under the
following labels: Poro-Klean(R), Micro-Screen(R), Auto-Klean(R), CTG-Klean(TM),
and DuoFLO(TM).

Housings and Systems: We design and manufacture a wide variety of filter
housings to suit specific process and customer applications. The housings can be
of plastic or metal construction utilizing a broad range of materials

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including polypropylene, PVC, nylon, aluminum, copper, brass, steel, stainless
steel and other specialized metals, such as titanium.

         Specialized designs include sanitary, electropolished and coated
finishes for chemical resistance and ease of sterilization, sanitization or
cleaning. We supply a broad range of standard housings manufactured from type
316 stainless steel in sanitary, polished and electropolished finishes for
enhancing pharmaceutical and electronic applications. Finish specifications can
be measured in terms of Roughness Average (Ra) with average variations in
surface finish measured in microns down to 0.45 micron, the size of small
bacteria.

         We design and manufacture proprietary housings and systems such as
CTG-Klean(TM) with patented features and a totally enclosed disposable filter
media pack for use in critical applications where housing cleanliness is
essential or when physical separation of toxic or corrosive chemicals from the
metal housing is desired.

         Our range of housings are designed and manufactured to regulatory
pressure vessel codes, particularly for applications in the oil and gas,
refinery and petrochemical industries. We design and market housings to meet the
local regulatory requirements in most countries.

BACKLOG: Our backlog on October 31, 2003 was $21.9 million as compared to $18.2
million as of the same date the previous year. Due to the relatively short
manufacturing cycle and our use of wholesale distributors as well as general
industry practice, backlog, which typically represents less than 30 days of
shipments, is not deemed to be significant. A substantial portion of our
revenues result from orders received and product sold in the same month.

COMPETITION: The markets in which we compete are highly competitive. We compete
with many domestic and international filtration companies in our global markets
including some which are larger and which possess greater resources. No one
company has a significant presence in all of our markets. The principal methods
of competition are product specifications, performance, quality, knowledge,
reputation, technology, distribution capabilities, service and price. Some of
our other competitors are multi-line companies with other principal sources of
income, some of which have substantially greater resources than the Company.
Other competitors are local product assemblers or service companies that
purchase components and supplies such as valves and tanks from more specialized
manufacturers. Through our S.A.S.S. teams, we have developed many products by
collaborating with our customers throughout the design and development process.
We believe that these relationships provide us with a competitive advantage over
other manufacturers.

RESEARCH AND DEVELOPMENT: Our research, development, and engineering activities
are conducted in our own laboratories, supplemented by on-site development and
application of custom design and other technical skills. Our research,
development and engineering expenditures, which consisted mainly of the
development of new products, product applications and manufacturing processes
for fiscal years 2003, 2002, and 2001 were approximately $15.0, $14.7 and $13.7,
respectively, and 5.2 percent, 5.7 percent and 5.6 percent of net sales,
respectively. We also incur additional internal costs relating to our sales and
service personnel for product development.

MANUFACTURING: Our manufacturing is largely vertically integrated, using unique,
proprietary and patented processes, with many of the major components of our
filtration units manufactured and assembled in our own plants. We have begun to
outsource a limited amount of our manufacturing processes, such as segments of
metal housing manufacturing. We believe that we generally have sufficient
manufacturing capacity for the foreseeable future. We have developed a new, more
efficient membrane manufacturing process that we believe provides a competitive
advantage through the production of superior products at lower costs. Other than
our facilities in Singapore and China, all of our manufacturing facilities are
ISO 9002 certified.

RAW MATERIAL SUPPLIERS: The primary raw materials used by the Company are
cotton, nylon, acrylic, cellulose, resins, plastics and metals. We have not
experienced a shortage of any of our raw materials in the past three years. We
believe that there is an adequate supply of all of our raw materials at
competitive prices from a variety of suppliers.

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DISTRIBUTION AND SALES: We have approximately 150 independent distributors of
our products in 65 countries. Distributors represent the primary channel in the
marketing of our healthcare and fluid processing products. We have agreements
with all of our major distributors in the United States. In certain markets
outside the United States, we use dedicated sales people. Our potable water
products are sold directly to wholesalers, such as plumbing suppliers, water
quality dealers and major resellers, and through manufacturing representatives.

         Agreements with our United States distributors are usually for a period
of two years. Such agreements usually assign an exclusive territory, prohibit
distributors from carrying competing products, require that distributors share
market and customer related information other than pricing with us, and require
distributors to carry an adequate stock of our products. We do not believe that
the loss of any one of our distributors would have a significant adverse effect
on the Company. Our top ten customers accounted for approximately 28.8 percent
of our total sales in fiscal year 2003.

         Whirlpool accounted for approximately 14.3 percent, 13.2 percent and
11.5 percent of sales during the fiscal years ended October 31, 2003, 2002 and
2001, respectively. We believe that no other customers account for more than ten
percent of sales. As of October 31, 2003, the Company employed approximately 420
people as sales people. Of such employees, approximately 280 are located
overseas.

TRADEMARKS AND PATENTS: Trademarks and brand name recognition are important to
the Company. We generally own the trademarks under which our products are
marketed. We have registered our trademarks and will continue to do so as they
are developed or acquired. We have approximately 400 registered trademarks
throughout the world.

         We have approximately 290 active patents throughout the world and more
than 200 patent applications pending worldwide. Additionally, we rely on
proprietary, non-patented technologies to a certain extent. Certain of our
employees sign non-disclosure and assignment of proprietary rights agreements.

         We protect our intellectual property and believe there is significant
value associated with it. However, we believe that the loss of one or more of
our trademarks and patents would not have a material adverse effect, as we are
not heavily dependent on any one or few and we are continually expanding our
intellectual estate through new additions.

SEASONALITY: Our business is typically not seasonal. However, sales in the first
quarter of each fiscal year tend to be lower than the other quarters due to the
holiday season and year-end distributor inventory reductions.

GOVERNMENT REGULATIONS: We believe that we are in substantial compliance with
applicable regulations of Federal, state and local authorities regulating the
handling of specified substances and the discharge of materials into the
environment.

         We manufacture certain filtration products that are used as components
in medical devices and we must use the Food and Drug Administration ("FDA")
listed materials in the manufacture of these products. Additionally, we maintain
Drug Master File ("DMF") files on certain products sold into the health care
market.

         Certain medical devices marketed and manufactured by our customers are
subject to extensive regulation by the FDA and, in some instances, by foreign
governments. Noncompliance with FDA requirements can result in, among other
things, fines, injunctions, civil penalties, recall or seizure of products,
total or partial suspension of production, failure of the government to grant
pre-market clearance or pre-market approval for devices, withdrawal of marketing
approvals and criminal prosecution. Before a new device can be introduced into
the market, the manufacturer must generally obtain FDA clearance through either
a 510(k) notification or pre-market approval application ("PMA"). A 510(k)
clearance will be granted if the submitted information establishes that the
proposed device is "substantially equivalent" to a legally marketed Class I or
II medical device, or to a Class III medical device for which the FDA has not
called for PMAs. The FDA recently has been requiring a more rigorous
demonstration of

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substantial equivalence than in the past. It generally takes from four to twelve
months from submission to obtain a 510(k) clearance, but it may take longer. The
FDA may determine that a proposed device is not substantially equivalent to a
legally marketed device, or that additional information is needed before a
substantial equivalence determination can be made.

         In many areas the sale and promotion of water treatment devices is
regulated at the state level by product registration, advertising restrictions,
water testing, product disclosure and other regulations specific to the water
treatment industry. In some local areas certain types of water treatment
products, including those manufactured by us, are restricted because of a
concern with the amount and type of contaminants per volume of water they
discharge as locally regulated.

ENVIRONMENTAL MATTERS: Compliance with foreign, Federal, state and local laws
and regulations enacted to regulate the handling of and the discharge of
specified materials into the environment has not had, and is not expected to
have, a material effect upon our business.

EMPLOYEES: At October 31, 2003, we employed approximately 1,800 people worldwide
(exclusive of employees of independent distributors), with approximately 980
employees in the United States and approximately 820 employees in other
countries.

(d) Financial information about foreign and domestic operations and export
sales.

         See Note 9 to the financial statements on pages 33-35 of the 2003
Annual Report to Stockholders which is incorporated herein by reference.

CAUTION CONCERNING FORWARD-LOOKING STATEMENTS: Because we want to provide
shareholders with more meaningful and useful information, this annual report on
Form 10-K contains statements relating to future events and the predicted
performance of the Company which may constitute forward-looking statements, as
defined under the Private Securities Litigation Act. We have tried, wherever
possible, to identify these forward-looking statements by using words such as
"anticipates," "believes," "estimates," "plans,", "expects," and similar
expressions. These statements reflect our current beliefs and are based on
information currently available to us. Accordingly, these statements are subject
to risks and uncertainties which could cause our actual results performance or
achievements to differ materially from those expressed in, or implied by, these
statements. These risks and uncertainties include the following: economic and
political conditions in foreign countries in which we conduct a substantial part
of our operations and other risks associated with international operations
including taxation policies, credit risk, exchange rate fluctuations and the
risk of expropriation; our ability to protect our technology, proprietary
products and manufacturing techniques; volumes of shipments of our products,
changes in our product mix and product pricing; continuing beneficial
relationships with customers; cost of raw materials; the rate of economic and
industry growth in the United States and the other countries in which we conduct
our business; changes in technology, changes in legislative, regulatory or
industrial requirements and risks generally associated with new product
introduction and applications; and domestic and international competition in our
global markets. We assume no obligation to publicly release revisions to the
forward-looking statements to reflect new events or circumstances.

                SECTION 16(A). AUDIT COMMITTEE FINANCIAL EXPERT

         Our Audit Committee consists of four Directors, Messrs. John M. Galvin,
who is Chairman of the Committee, David L. Swift, C. Edward Migley, and Dr.
Charles L. Cooney. All of these Directors are independent as defined in the rule
of the Securities and Exchange Commission pursuant to the Securities Exchange
Act of 1934, as amended.

         The responsibilities of our Audit Committee, as more fully discussed in
its Charter, are to assist the Board of Directors in fulfilling its oversight
responsibilities for the financial reporting process, the system of internal
control, the audit process, and the Company's process for monitoring compliance
with laws and regulations.

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         The Board of Directors of the Company has determined that at least one
member of the Audit Committee, Mr. John M. Galvin, is an audit committee
financial expert. An audit committee financial expert is a person who has (i)
and understanding of generally accepted accounting principles and financial
statements, (ii) the ability to assess the general application of said
principles in connection with the accounting for estimates, accruals and
reserves, (iii) experience preparing, auditing, analyzing or evaluating
financial statements of comparable breadth and complexity to the Company's or
experience supervising others who do, (iv) an understanding of internal controls
and procedures, and (v) an understanding of audit committee functions.

                         SECTION 16(B). CODE OF ETHICS

         The Company has adopted a formal Code of Ethics including its Principal
Executives and Senior Financial Officers that applies to its Chief Executive
Officer, Chief Financial Officer and its Controller. The Company has posted this
Code of Ethics to its website, www.cuno.com, and will provide a copy to any
person without charge upon request.

                             AVAILABLE INFORMATION

The Company provides free of charge access to its annual report on Form 10-K,
quarterly reports on Form 10-Q, current reports on Form 8-K and other SEC
filings, through its website, www.cuno.com, as soon as reasonably practicable
after such reports are electronically filed with the SEC.

The Company will also provide free of charge a copy of its 2003 Annual Report to
Shareholders upon written request to:

John A. Tomich
General Counsel and Secretary
CUNO Incorporated
400 Research Parkway
Meriden, CT 06450

Or by calling: 1-203-237-5541

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ITEM 2. PROPERTIES

         Our world headquarters is located in Meriden, Connecticut. This
facility also contains a manufacturing and assembly plant. The following table
sets forth the location and approximate size of our principal properties and
facilities, most of which are owned by the Company.

<TABLE>
<CAPTION>
                                                        Approximate
                                                       Facility Size
                     Location                            (Sq. Ft.)
----------------------------------------------------   -------------
<S>                                                    <C>
Meriden, Connecticut ...............................         189,000
Enfield, Connecticut ...............................         155,000
Stafford Springs, Connecticut ......................         165,000
Kita-Ibaragi, Japan ................................          40,000
Mairinque, Brazil ..................................          65,000
Calais, France .....................................          50,000
Mazeres, France ....................................          40,000
Sydney, Australia * ................................         265,000
Singapore** ........................................          18,546
Churubusco, Indiana ................................          47,000
Sucy en Brie, France ** ............................          20,000
Nantes, France **  .................................           4,600
Shanghai, China **  ................................           4,700
</TABLE>

*  10 percent of this facility is sublet to unrelated third parties.
** Leased facility.

         In addition to the properties listed above, we lease one facility in
the United States and approximately 16 facilities outside the United States.
These facilities are generally used as warehouses and/or sales offices.

ITEM 3. LEGAL PROCEEDINGS

         As of the date hereof there is no pending litigation of a material
nature, other than ordinary routine litigation incidental to the business, to
which the Company or any of its subsidiaries is a party or which may affect the
income from, title, to, or possession of, any of their respective properties.

ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS.

         There were no matters submitted to a vote of stockholders during the
fourth quarter of fiscal year 2003.

                                       10
<PAGE>

                                     PART II

ITEM 5.  MARKET FOR THE REGISTRANT'S COMMON EQUITY AND RELATED STOCKHOLDER
         MATTERS

The portion of the 2003 Annual Report to Stockholders appearing on page 1 under
the heading "Market Data" is incorporated herein by reference.

ITEM 6.  SELECTED FINANCIAL DATA

The financial data on page 7 of the 2003 Annual Report to Stockholders,
captioned "Summary of Financial Data" is incorporated herein by reference.

ITEM 7.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
         OF OPERATIONS 2003-2001

The following portions of the 2003 Annual Report to Stockholders are
incorporated herein by reference:

(a) All of the material on pages 8-17 under the heading "Management's Discussion
and Analysis of Financial Condition and Results of Operations".

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

Information appearing under the caption "Market Risk Disclosures" appearing on
page 16 of the 2003 Annual Report to Stockholders is incorporated herein by
reference.

ITEM 8.  FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

The consolidated financial statements of the Company and report of independent
auditors included on pages 18-22 of the Annual Report to Stockholders for the
fiscal year ended October 31, 2003 are incorporated herein by reference.

Quarterly Results of Operations on page 38 of the 2003 Annual Report to
Stockholders is incorporated herein by reference.

ITEM 9.  CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
         FINANCIAL DISCLOSURE.

         None

ITEM 9A. CONTROLS AND PROCEDURES

As of October 31, 2003, an evaluation of the effectiveness of the design and
operation of the Company's disclosure control and procedures was performed under
the supervision and with the participation of the Company's management,
including the Chief Executive Officer and Chief Financial Officer. Based on that
evaluation, the Company's management, including the Chief Executive Officer and
the Chief Financial Officer, concluded that the Company's disclosure controls
and procedures were effective as of October 31, 2003. No significant changes in
the Company's internal controls or in other factors that have occurred that
could significantly affect controls subsequent to October 31, 2003 through the
date of the filing of this report.

                                       11
<PAGE>

                                    PART III

ITEM 10. DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

         Information regarding the Directors of the Registrant required by
Section 16 of the Exchange Act is incorporated by reference to the definitive
Proxy Statement of the Registrant, required to be filed with the Commission
within 120 days of October 31, 2003, in connection with the annual meeting of
stockholders to be held on March 4, 2004.

         The principal executive officers of the Company and their recent
business experience are as follows:

<TABLE>
<CAPTION>
           Name                                 Office Held                             Age
-----------------------------    ---------------------------------------------------    ---
<S>                              <C>                                                    <C>
Mark G. Kachur...............    Chairman of the Board of Directors, President and       60
                                 Chief Executive Officer

Frederick C. Flynn, Jr.......    Senior Vice President - Finance and Administration,     53
                                 Chief Financial Officer and Assistant Secretary

Thomas J. Hamlin.............    Senior Vice President, Research & Development           42

Timothy B. Carney............    Vice President, and General Manager and President -     51
                                 North America Water Group

Anthony C. Doina.............    Vice President - Worldwide Fluid Processing             47

John A. Tomich...............    General Counsel and Secretary                           46
</TABLE>

         None of the officers are related and they are elected from year to year
or until their successors are duly elected and qualified.

         Mark G. Kachur. Mr. Kachur is the Chairman of the Board of Directors,
President and Chief Executive Officer of the Company. Mr. Kachur has been a
director of the Company since July 1996. Since joining the Company in 1994, Mr.
Kachur has been a Senior Vice President of Commercial Intertech and President
and Chief Operating Officer of the Company. From 1992 until 1994, he was
President and CEO of Biotage, Inc., from 1971 to 1991, he was with Pall
Corporation, the last seven years as a Group Vice President. He holds a bachelor
of science degree in Mechanical Engineering from Purdue University and a
master's degree in Business Administration from the University of Hartford.

         Frederick C. Flynn, Jr. Mr. Flynn is the Senior Vice President -
Finance and Administration, Chief Financial Officer, and Assistant Secretary of
the Company. Prior to joining CUNO in January 1999, Mr. Flynn was Senior Vice
President and Chief Financial Officer of GE Capital Information Technology
Solutions. From 1989 to 1995 Mr. Flynn was Vice President and Treasurer of
United Technologies Corporation. He holds a bachelor of science degree in
Economics from Boston College and a master's degree in Business Administration
from the University of Connecticut.

                                       12
<PAGE>

         Thomas J. Hamlin. Mr. Hamlin is the Senior Vice President of Research
and Development. Since joining the Company in 1983, Mr. Hamlin has held a
variety of positions including managerial positions in manufacturing and plant
operations as well as Vice President of Product Development. Mr. Hamlin holds a
bachelor of science degree in Mechanical Engineering from Rensselaer Polytechnic
Institute and a master's degree in Business Administration from RPI, Hartford
Graduate Center.

         Timothy B. Carney. Mr. Carney is the Company's Vice President, and
General Manager and President of the North American Water Group. Previous to
this, Mr. Carney served as the Company's Controller and effective November 1999,
became Senior Vice President - Finance and Administration of the Company's
worldwide Water Group. From 1993 until joining the Company, he served Commercial
Intertech as CUNO Inc. Group Controller and from 1989 until 1993 he served
Commercial Intertech as General Manager and Controller of Water Factory Systems.
He holds a bachelor of science degree in Economics and a master's degree in
Business Administration from Youngstown State University.

         Anthony C. Doina. Mr. Doina is the Vice President -- Worldwide Fluid
Processing. Since joining the Company in 1994, Mr. Doina has also served in the
capacity of Vice President of Process Sales. From 1978 until 1994 he was
employed by Pall Corporation, serving in a number of positions in Research and
Development, Marketing, and Sales (Vice President of Sales). Prior to joining
the Company, Mr. Doina had over 16 years of sales experience in the filtration
industry. Mr. Doina holds a bachelor of science degree in Chemistry from the
University of Stony Brook.

         John A. Tomich. Mr. Tomich is General Counsel and Secretary of the
Company. Before joining CUNO Incorporated after the spin-off from Commercial
Intertech he was Counsel and Assistant Secretary for Commercial Intertech, where
he had been employed since January 1990 and had been involved extensively with
the legal matters affecting CUNO. He holds a bachelor of Engineering degree in
Mechanical Engineering from Youngstown State University and Juris Doctor degree
from the University of Akron, School of Law. He is a licensed patent attorney.

ITEM 11. EXECUTIVE COMPENSATION

         The information required by this item is incorporated by reference to
the definitive Proxy Statement of the Registrant, which is required to be filed
with the Commission within 120 days of October 31, 2003, in connection with the
annual meeting of stockholders to be held on March 4, 2004.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

         The information required by this item is incorporated by reference to
the definitive Proxy Statement of the Registrant, which is required to be filed
with the Commission within 120 days of October 31, 2003, in connection with the
annual meeting of stockholders to be held on March 4, 2004.

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

         The information required by this item is incorporated by reference to
the definitive Proxy Statement of the Registrant, which is required to be filed
with the Commission within 120 days of October 31, 2003, in connection with the
annual meeting of stockholders to be held on March 4, 2004.

                                       13
<PAGE>

                                     PART IV

ITEM 14. PRINCIPAL ACCOUNTANT FEES AND SERVICES

         The information required by this item is incorporated by reference to
the definitive Proxy Statement of the Registrant, which is required to be filed
with the Commission within 120 days of October 31, 2003, in connection with the
annual meeting of stockholders to be held on March 4, 2004.

ITEM 15  EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K

(a) DOCUMENTS FILED AS PART OF THIS REPORT:

(1) The following consolidated financial statements of CUNO Incorporated
        included in its 2003 Annual Report to Shareholders are incorporated by
        reference in Item 8:

<TABLE>
<CAPTION>
                                                          Page Number
                                                         In This Report
                                                         --------------
<S>                                                      <C>
Consolidated Statements of Income -
  Years ended October 31, 2003,
  2002, and 2001......................................          19

Consolidated Balance Sheets as of
  October 31, 2003 and 2002...........................          20

Consolidated Statements of Stockholders'
  Equity - Years ended October 31,
  2003, 2002, and 2001................................          21

Consolidated Statements of Cash Flows -
  Years ended October 31, 2003, 2002, and 2001........          22

Notes to Consolidated Financial Statements............       23-38

(2) The following financial statement schedule of CUNO Incorporated is included
    in Item 14 (d):

        Schedule II Valuation and Qualifying
        Accounts......................................         S-1
</TABLE>

         All other schedules for which provision is made in the applicable
accounting regulation of the Securities and Exchange Commission are not required
under the related instructions or are inapplicable and therefore have been
omitted.

           (3) Exhibits

         (i) 3.1 -- Articles of Incorporation Filed as of April 17, 1992
         Incorporated by reference to Exhibit 3.1 to the Company's Form 10 (as
         filed with Amendment No. 2 thereto dated August 20, 1996).

                                       14
<PAGE>

         (10 ) -- Material Contracts

(i)      10.9 Termination and Change of Control Agreement - Mark G. Kachur dated
         October 1, 1996
(iii)    10.12 Termination and Change of Control Agreement - Timothy B. Carney
         dated October 1, 1996, as amended October 31, 1997.
(i)      10.13 Termination and Change of Control Agreement - John A. Tomich
         dated October 1, 1996
         (ii)     10.15 CUNO Incorporated Executive Management Incentive Plan
         (ii)     10.16 CUNO Incorporated Management Incentive Plan
         (iii)    10.17 CUNO Incorporated Savings and Retirement Plan
         (iv)     10.20 CUNO Incorporated Nonqualified Deferred Compensation
                  Plan for Mark G. Kachur
         (v)      10.21 Termination and Change of Control Agreement - Frederick
                  C. Flynn, Jr. dated January 21, 1999
         (vi)     10.23 Employment Agreement - Frederick C. Flynn, Jr.
         (vii)    10.24 Employment Agreement - Michael C. Croft
(viii)   10.25 Employment Agreement - Mark G. Kachur
(ix)     10.26 Employment Agreement - Frederick C. Flynn, Jr.
(ix)     10.27 Employment Agreement - Thomas J. Hamlin
(x)      10.28 Amended Employment Agreement - Mark G. Kachur
(xi)     10.29 CUNO Incorporated Code of Ethics
         10.30 Amended Employment Agreement - Mark G. Kachur
            13 - Certain sections of the Annual Report to Shareholders for the
            year ended October 31, 2003.
            21 - Subsidiaries of the Registrant
            23 - Consent of Independent Auditors
31.1* Certification of Mark G. Kachur pursuant to Section 302 of the
Sarbanes-Oxley Act of 2003
31.2* Certification of Frederick C. Flynn pursuant to Section 302 of the
Sarbanes-Oxley Act of 2003
32.1* Certification of Chief Executive Officer pursuant to 18 U.S.C. sec. 1350,
as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
32.2* Certification of Chief Financial Officer pursuant to 18 U.S.C. sec. 1350,
as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.

--------------------------
         (i) Incorporated by reference to the registrant's Annual Report on Form
10-K, as amended, filed with the Securities and Exchange Commission on January
23, 1997.
         (ii) Incorporated by reference to the Registrant's Registration
Statement on Form S-1, as amended, filed with the Securities and Exchange
Commission on February 27, 1997.
         (iii) Incorporated by reference to the registrant's Annual Report on
Form 10-K, filed with the Securities and Exchange Commission on January 28,
1998.
         (iv) Incorporated by reference to the registrant's Annual Report on
Form 10-K, filed with the Securities and Exchange Commission on January 29,
1999.
         (v) Incorporated by reference to the registrant's Quarterly Report on
Form 10-Q, filed with the Securities and Exchange Commission on April 4, 1999.
         (vi) Incorporated by reference to the registrant's Quarterly Report on
Form 10-Q, filed with the Securities and Exchange Commission on June 4, 1999.
         (vii) Incorporated by reference to the registrant's Quarterly Report on
Form 10-Q, filed with the Securities and Exchange Commission on September 11,
2000.
         (viii) Incorporated by reference to the registrant's Annual Report on
Form 10-K, filed with the Securities and Exchange Commission on January 16,
2002.
         (ix) Incorporated by reference to the registrant's Quarterly Report on
Form 10-Q, filed with the Securities and Exchange Commission on February 19,
2002.
         (x) Incorporated by reference to the registrant's Quarterly Report on
Form 10-Q, filed with the Securities and Exchange Commission on August 21, 2002.

                                       15
<PAGE>
         (xi) Incorporated by reference to the registrant's Annual Report on
Form 10-K, filed with the Securities and Exchange Commission on December 13,
2002.

(b) Reports on Form 8-K for the quarter ended October 31, 2003.

         We filed a Report on Form 8-K, dated August 20, 2003, under "Item 5.
Other Events," reporting our financial results for the third quarter ended July
31, 2003

         We filed a Report on Form 8-K, dated October 2, 2003, under "Item 4.
Change in Registrant's Certifying Public Accountant," reporting the dismissal of
Ernst & Young LLP as our independent accountants effective after the filing of
the Annual Report on Form 10-K for the year ended October 31, 2003, and the
appointment of PricewaterhouseCoopers LLP as our successor independent
accountants.

         We filed a Report on Form 8-K, dated October 2, 2003, under "Item 4.
Change in Registrant's Certifying Public Accountant," reporting the dismissal of
Ernst & Young LLP as the independent accountants of the CUNO Incorporated
Savings and Retirement Plan (the "Plan") and the appointment of
PricewaterhouseCoopers LLP as the successor independent accountants of the Plan.

         Additional information relating to management contracts and
renumerative plans is contained in Note 10 - Stock Options and Awards of the
Notes to Consolidated Financial Statements on pages 35-36 of the 2003 Annual
Report to Stockholders.

                                       16
<PAGE>
SIGNATURES

         Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized.

                                CUNO Incorporated

Date: December 18, 2003

/s/ Mark G. Kachur                                 /s/ Frederick C. Flynn, Jr.
----------------------------                       -----------------------------
Mark G. Kachur                                     Frederick C. Flynn, Jr.
Chairman of the Board                              Senior Vice President --
of Directors, President, and                       Finance and Administration,
Chief Executive Officer                            Chief Financial Officer,
                                                   and Assistant Secretary

         Pursuant to the requirements of the Securities Exchange Act of 1934,
this report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated above.

<TABLE>
<CAPTION>
          Name                Title            Date
-------------------------    --------    -----------------
<S>                          <C>         <C>
Joel B. Alvord*              Director    December 18, 2003

Charles L. Cooney, Ph.D.*    Director    December 18, 2003

Frederick C. Flynn, Jr.*     Director    December 18, 2003

John A. Galvin*              Director    December 18, 2003

Mark G. Kachur*              Chairman    December 18, 2003

C. Edward Midgley*           Director    December 18, 2003

David L. Swift*              Director    December 18, 2003
</TABLE>

*By: /s/ John A. Tomich
     ------------------------------
     John A. Tomich
     Attorney-in-Fact, Pursuant to
     Power of Attorney

                                       17
<PAGE>


                SCHEDULE II -- VALUATION AND QUALIFYING ACCOUNTS

                                CUNO INCORPORATED
                  YEARS ENDED OCTOBER 31, 2003, 2002, AND 2001

<TABLE>
<CAPTION>
                   COLUMN A                      COLUMN B                      COLUMN C                   COLUMN D       COLUMN E
------------------------------------------------------------------------------------------------------------------------------------
                                                                             ADDITIONS
                                                                  ------------------------------------
                                            BALANCE AT BEGINNING  CHARGED TO COSTS   CHARGED TO OTHER                 BALANCE AT END
                 DESCRIPTION                     OF PERIOD          AND EXPENSES    ACCOUNTS - DESCRIBE  DEDUCTIONS      OF PERIOD
====================================================================================================================================
<S>                                         <C>                   <C>               <C>                 <C>           <C>
Year ended October 31, 2003
Deducted from asset accounts:
Allowance for doubtful accounts receivable       $1,406,268         $  355,615         $176,839(D)      $233,192(A)     $1,705,530
                                                 ==========         ==========         ========         ========        ==========
Valuation allowance for deferred
income tax assets                                $1,465,000         $  211,000(B)      $      0         $      0        $1,676,000
                                                 ==========         ==========         ========         ========        ==========

Year ended October 31, 2002
Deducted from asset accounts:
Allowance for doubtful accounts receivable       $1,336,490         $  279,134         $ 13,272(D)      $222,629(A)     $1,406,268
                                                 ==========         ==========         ========         ========        ==========
Valuation allowance for deferred income
tax assets                                       $  116,000         $1,349,000(B)      $      0         $      0        $1,465,000
                                                 ==========         ==========         ========         ========        ==========

Year ended October 31, 2001
Deducted from asset accounts:
Allowance for doubtful accounts receivable       $1,394,685         $  133,384         $(87,204)(D)     $104,375(A)     $1,336,490
                                                 ==========         ==========         ========         ========        ==========
Valuation allowance for deferred income
tax assets                                       $  350,000         $        0(B)      $      0         $234,000(C)     $  116,000
                                                 ==========         ==========         ========         ========        ==========
</TABLE>

(A) Uncollectible accounts written off, net of recoveries.

(B) Establishment of valuation allowance for operating loss
    carryforwards.

(C) Net operating loss carryforwards utilized.

(D) Changes in foreign currency.

                                       S-1