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                                                                      EXHIBIT 14

                           KEITHLEY INSTRUMENTS, INC.

                       CODE OF BUSINESS CONDUCT AND ETHICS

                             ADOPTED AUGUST 27, 2003

Keithley Instruments, Inc. values its reputation for integrity. Our directors,
officers and employees shall at all times conduct themselves with the highest
regard for ethics, integrity and applicable laws. This Code applies to the
Company's employees, officers and directors regarding a wide range of topics and
is generally designed to:

      -     Require honest and ethical conduct, particularly where actual or
            apparent conflicts of interest could arise;

      -     Ensure fair, accurate and balanced reporting of financial and other
            information to the SEC and the public;

      -     Promote compliance with all laws in the cities, states and countries
            in which we operate;

      -     Promote appropriate use and treatment of tangible and intangible
            property of the Company, including its trade secrets and proprietary
            information;

      -     Encourage respect for the individuals, property and other rights of
            our employees, customers, suppliers and competitors.

1.    Compliance With Laws and Regulations; Insider Trading.

We strive to be in compliance with the letter and spirit of all laws and
regulations that may apply to our business in the cities, states and countries
in which we operate. Management has access to legal advice in every location in
which we operate, and employees should seek advice as is necessary where there
are questions or ambiguities about laws or their application to particular
activities.

It is both unethical and illegal to buy, sell, trade or otherwise participate in
transactions involving Keithley Common Shares or the securities of another
company while in possession of material non-public information concerning
Keithley or another company. We have a separate Insider Trading Policy that is
distributed annually to all employees. If you have any questions regarding the
propriety of any transaction in Keithley Common Shares or in any other security
transaction, please contact the Chief Financial Officer.

2.    Conflicts of Interest.

A "conflict of interest" exists when a person's private interest interferes or
appears to interfere in any way with the interests of the Company. A conflict of
interest may arise when a director, officer or employee takes actions or has
interests that may make it difficult to perform his or her duties or obligations
for the Company objectively. Conflicts of interest can also arise when a
director, officer or employee receives improper

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personal benefits as a result of his or her position with the Company. In
particular, a conflict of interest can arise when an employee, officer or
director is employed by or accepts remuneration from any competitor or any
business that has a business relationship with the Company or has a material
financial interest in any transaction in which the Company is a party. All
employees, officers and directors are expected to avoid all situations that
might lead to such conflicts of interest. Employees are encouraged to talk to
their supervisors, managers or other appropriate personnel about potential
conflicts of interest they may be facing. Directors and officers should discuss
such matters with the Company's Chief Executive Officer or Chief Financial
Officer.

3.    Confidentiality; Protection and Proper Use of Company Assets.

All employees, officers and directors must maintain the strict confidentiality
of confidential information entrusted to the them by the Company or its
customers or suppliers, except when disclosure is authorized by the Chief
Executive Officer or Chief Financial Officer or when required by applicable laws
or regulations. Confidential information includes all non-public information
that may be of use to competitors or could be harmful to the Company or its
customers if disclosed. It also includes information that suppliers, customers
and other business partners have entrusted to us. The obligation to preserve
confidential information continues even after employment ends. Confidential
information includes, but is not limited to, the following:

      -     Sales rates, cost or profit data for any product or business line;

      -     The existence of or information in contracts in customers or
            suppliers;

      -     Information concerning products under development or previously
            investigated and abandoned, including product profitability
            estimates, product scheduling and market research reports;

      -     Information contained in laboratory notebooks, department reports,
            correspondence, business agreements and any similar data not known
            in the trade;

      -     Proprietary methods or equipment used by the Company in connection
            with quality control, production techniques and product development;

      -     Pricing formulas, cost information and other data the Company uses
            to formulate prices.

The Company is often a party to non-disclosure agreements with customers,
suppliers and others. The purpose of such agreements is to protect confidential
or sensitive information which is given and received. Employees, officers and
directors aware of such agreements should exercise care in using confidential
information received including with whom the information is shared.

All employees should endeavor to protect the Company's tangible assets and its
intellectual property and other intangible assets and insure their efficient
use. Any suspected incident of fraud or theft should be immediately reported.

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The obligation of employees to protect the Company's assets includes its
proprietary information. This includes intellectual property such as trade
secrets, patents, trademarks and copyrights, as well as business, marketing and
service plans, engineering and manufacturing ideas, designs, databases, records,
salary information and any unpublished financial data and reports. Unauthorized
use or distribution of this information violates Company policy. It may also
result in civil or criminal penalties. All employees are required to assign to
the Company their entire right, title and interest to all inventions that the
employee may make or conceive, either solely or jointly with others, during his
employment with the Company which are within the scope of the business of the
Company and the conception of which involved use of corporate information,
materials or time.

4.    Accounting and Recordkeeping.

All the Company's books, records, accounts and financial statements must be
maintained in reasonable detail, must appropriately reflect the Company's
transactions and must conform both to applicable legal requirements and to the
Company's systems of internal controls.

Business records and communications, even those intended to be confidential,
often become public. Accordingly, it is important to avoid exaggeration,
derogatory remarks or inappropriate characterizations of people or circumstances
that could be misunderstood. This applies to emails and informal internal memos
as well as formal reports.

The Company requires honest and accurate recording and reporting of business
expense accounts, which must be documented and recorded accurately and regularly
in accordance with Company policies. If you are not sure whether a particular
item is a legitimate business expense, ask your supervisor or the Company's
controller.

Senior management must be informed promptly of all matters that might be
considered sensitive in preserving the Company's reputation and assets.
Similarly, there shall be no concealment of information from the Company's
independent auditors.

5.    Corporate Opportunities.

Employees, officers and directors are prohibited from taking for themselves
personally opportunities that are discovered through their service for the
Company or through the use of corporate property, information or position
without in each case the consent of the Board of Directors. No employee may use
corporate property, information or position for improper personal gain and no
employee may compete with the Company directly or indirectly.

6.    Fair Competition and Fair Dealing.

We seek to outperform our competition fairly, openly and honestly. We seek
competitive advantages through superior performance, but never through unethical
or illegal business practices. Stealing proprietary information or inducing
inappropriate disclosures by past or present employees of other companies is
prohibited. Each employee should endeavor to respect the rights of and deal
fairly with the Company's customers, suppliers and competitors and their
respective employees.

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7.    Business Gifts and Entertainment.

The purpose of business entertainment and gifts in a commercial setting is to
create good will and sound working relationships. No employee, officer or
director should accept any gifts of more than a token nature from any person or
business who does or wishes to do business with the Company and should not give
gifts of more than a token nature to anyone with which the Company wishes to do
business. The following are permissible:

      -     Accepting a gift in recognition of a commonly recognized event or
            occasion (such as promotion, new job, wedding, retirement or
            holiday), so long as the gift is not in cash and does not exceed a
            value that would be customary for the occasion;

      -     Accepting something of value if the benefit of it is available to
            the general public under the same conditions on which it is made
            available to you;

      -     Accepting meals, refreshments, travel arrangements and
            accommodations and entertainment of a reasonable value in the course
            of a meeting or other occasion to conduct business or foster
            business relations.

In addition, acts of hospitality towards all public officials or persons with
whom the Company does business should be of such a scale and nature as to avoid
compromising the integrity or impugning the reputation of the official or the
Company. All such acts should be performed with the expectation that they will
become a matter of public knowledge.

8.    Payments to Government Personnel.

The Foreign Corrupt Practices Act prohibits giving anything of value, directly
or indirectly, to officials of foreign governments or foreign political
candidates in order to obtain or retain business. It is strictly prohibited to
make illegal payments to government officials of any country. In addition, there
are U.S. laws regulating gratuities which may be accepted by U.S. governmental
personnel. The promise, offer or delivery to an official or employee of the U.S.
government or a gift, favor or other gratuity in violation of these rules would
not only violate the Company's policy but could also result in civil and
criminal penalties.

9.    Waivers and the Reporting of Illegal or Unethical Behavior.

Any waiver of this code for executive officers or directors may only be made by
the Board or a Committee of the Board authorized to do so and will be promptly
disclosed as required by applicable law or NYSE listing standards. Employees are
encouraged to talk to supervisors, managers or other appropriate personnel about
any illegal or unethical behavior they observe. It is the policy of the Company
not to permit retaliation for reports of misconduct by others made in good faith
by employees. Employees are expected to cooperate in internal investigations of
misconduct.