SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549
                  _____________________________________________
                                    FORM 10-K

    (mark one)
    [ X ] Annual Report Pursuant to Section 13 or 15(d) of the Securities
          Exchange Act of 1934 for the fiscal year ended January 3, 1998

    [   ] Transition Report Pursuant to Section 13 or 15(d) of the Securities
          Exchange Act of 1934
                         Commission file number 1-12179

                         THERMO BIOANALYSIS CORPORATION
             (Exact name of Registrant as specified in its charter)

    Delaware                                                       85-0429899
    (State or other jurisdiction of                          (I.R.S. Employer
    incorporation or organization)                        Identification No.)

    504 Airport Road
    Santa Fe, New Mexico                                           87504-2108
    (Address of principal executive offices)                       (Zip Code)
       Registrant's telephone number, including area code: (781) 622-1000
           Securities registered pursuant to Section 12(b) of the Act:

          Title of each class         Name of exchange on which registered
      ----------------------------    ------------------------------------
      Common Stock, $.01 par value          American Stock Exchange

           Securities registered pursuant to Section 12(g) of the Act:
                                      None
    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 the Registrant's knowledge, in definitive proxy
    or information statements incorporated by reference into Part III of this
    Form 10-K or any amendment to this Form 10-K. [   ]

    The aggregate market value of the voting stock held by nonaffiliates of
    the Registrant as of January 30, 1998, was approximately $40,585,000.

    As of January 30, 1998, the Registrant had 9,774,718 shares of Common
    Stock outstanding (11,074,718 pro forma shares).
                       DOCUMENTS INCORPORATED BY REFERENCE

    Portions of the Registrant's Annual Report to Shareholders for the year
    ended January 3, 1998, are incorporated by reference into Parts I and II.

    Portions of the Registrant's definitive Proxy Statement for the Annual
    Meeting of Shareholders to be held on June 1, 1998, are incorporated by
    reference into Part III.
PAGE
<PAGE>
                                     PART I

    Item 1. Business
            --------

    (a) General Development of Business
        -------------------------------

        Thermo BioAnalysis Corporation (the Company or the Registrant)
    designs, manufactures, and markets life sciences instrumentation,
    consumables, and information management systems, for use in biochemical
    research and production, as well as in clinical diagnostics. The
    Company's life sciences instrumentation and consumables are based on
    proprietary immunoassay, optical biosensor, polymerase chain reaction
    (PCR), liquid-handling, mass spectrometry, DNA amplification, capillary
    electrophoresis (CE), and radiation measurement technologies. The
    Company's information management systems subsidiary designs, implements,
    and supports laboratory information management systems (LIMS) and
    chromatography data systems. The Company was incorporated in February
    1995 as a wholly owned subsidiary of Thermo Instrument Systems Inc.
    Thermo Instrument is a majority-owned subsidiary of Thermo Electron
    Corporation.

        The Company's strategy is to develop and market a portfolio of
    instruments, consumables, and information management systems for
    biochemistry and other applications through the acquisition of
    complementary businesses and technologies and through research and
    development of innovative products. Since its incorporation in February
    1995, the Company acquired the Dynex Technologies division of Dynatech
    Corporation in February 1996, acquired the Affinity Sensors and
    LabSystems divisions of Fisons from Thermo Instrument, effective March
    29, 1996, and agreed to acquire the Labsystems OY, Hybaid, and Labsystems
    Japan divisions of Life Sciences International PLC (LSI) from Thermo
    Instrument, effective March 12, 1997. Dynex supplies automated systems,
    detection systems, and consumables to the immunoassay market. Affinity
    Sensors supplies optical biosensors used in life sciences research by the
    pharmaceutical and biotechnology industries, universities, and medical
    research institutes. LabSystems designs, implements, and supports LIMS
    and chromatography data systems used in research and development, quality
    assurance and control, and processing plants. Labsystems OY, based in
    Finland, manufactures microplate-based immunoassay instruments and
    liquid-handling equipment. Hybaid, based in the U.K., manufactures
    thermal cyclers and consumables for DNA amplification. Labsystems Japan
    distributes products manufactured by Labsystems OY, Hybaid, and other LSI
    companies. 

        In September 1996, the Company conducted an initial public offering
    of 1,670,000 shares of its common stock at $14.00 per share for net
    proceeds of $20.8 million. As of January 3, 1998, Thermo Instrument owned
    7,799,000 shares of the common stock of the Company, representing 70% of
    such stock outstanding. Such shares include the 1,300,000 shares issuable
    to Thermo Instrument in connection with the acquisition of the Labsystems
    OY and Hybaid divisions of LSI. Thermo Instrument develops, manufactures,
    markets, and services instruments and software used for identification
    and quantification of complex molecular compounds and elements in gases,
    liquids, and solids. Uses include pharmaceutical drug research and
    clinical diagnostics, monitoring and measuring environmental pollutants,
    industrial inspection, and test and control for quality assurance and 

                                        2PAGE
<PAGE>
    productivity improvement. In addition, Thermo Instrument develops,
    manufactures, markets, and services equipment for the measurement,
    preparation, storage, and automation of sample materials and photonics
    and vacuum components for original equipment manufacturers (OEMs). As of
    January 3, 1998, Thermo Electron owned 788,967 shares of the common stock
    of the Company, representing 7% of such stock outstanding. Of this
    amount, Thermo Electron purchased 729,200 shares in the open market
    during 1997*, for a total purchase price of $11.4 million. Thermo
    Electron provides analytical and monitoring instruments; biomedical
    products including heart-assist devices, respiratory-care equipment, and
    mammography systems; paper recycling and papermaking equipment;
    alternative-energy systems; industrial process equipment; and other
    specialized products. Thermo Electron also provides a range of services
    that include industrial outsourcing, particularly in
    environmental-liability management, laboratory analysis, and
    metallurgical processing; and conducts advanced-technology research and
    development.

    Forward-looking Statements

        Forward-looking statements, within the meaning of Section 21E of the
    Securities Exchange Act of 1934, are made throughout this Annual Report
    on Form 10-K. For this purpose, any statements contained herein that are
    not statements of historical fact may be deemed to be forward-looking
    statements. Without limiting the foregoing, the words "believes,"
    "anticipates," "plans," "expects," "seeks," "estimates," and similar
    expressions are intended to identify forward-looking statements. There
    are a number of important factors that could cause the results of the
    Company to differ materially from those indicated by such forward-looking
    statements, including those detailed under the heading "Forward-looking
    Statements" in the Registrant's 1997 Annual Report to Shareholders, which
    statements are incorporated herein by reference.

    (b) Financial Information About Industry Segments
        ---------------------------------------------

        The Company conducts business in one industry segment.

    (c) Description of Business
        -----------------------

        (i) Principal Products and Services
            -------------------------------

        The Company designs, manufactures, and markets instruments,
    consumables, and information management systems, for use in biochemical
    research and production, as well as in clinical diagnostics. The Company
    markets and distributes its products through a number of channels,
    including a direct sales force, independent sales representatives,
    distributors, and OEMs. The method of distribution is determined by
    product line, market size, and potential, as well as by local business
    convention, industry mix, and the availability of technically qualified
    representatives.

    * References to 1997, 1996, and 1995 herein are for the fiscal years
      ended January 3, 1998, December 28, 1996, and December 30, 1995,
      respectively.

                                        3PAGE
<PAGE>
        The Company focuses on three principal product areas: life sciences
    instrumentation, consumables, and information management systems.

    Life Sciences Instrumentation

        The Company designs, manufactures, and markets a broad range of
    instruments based on proprietary immunoassay, optical biosensor, PCR,
    mass spectrometry, DNA amplification, CE, and radiation measurement
    technologies. The Company's products include automated systems, detection
    systems, and consumables for the immunoassay market; optical biosensors;
    MALDI-TOF mass spectrometers; thermal cyclers; and CE systems,
    components, and accessories.

        The Company sells its life sciences instrumentation principally
    through its direct sales force, OEMs, dealerships, and distributors
    throughout the world. The Company maintains direct sales offices in
    several European countries, Canada, Japan, and the United States. The
    Company also sells through manufacturers' representatives.

        Molecular Interaction. The Company designs, manufactures, sells, and
    supports products for immunoassay testing. Immunoassays are studies
    performed for the qualitative and quantitative analysis of the molecular
    interaction between biological and other molecules. Immunoassay products
    are used in medical and pharmaceutical research; clinical diagnostics
    including tests for pregnancy, hepatitis, and HIV; veterinary medicine;
    agricultural diagnostics; water quality testing; and food and beverage
    testing. In 1997, the Company introduced a multi-analyte biosensor, IAsys
    Auto+ Advantage, and a combination luminescence and fluorescence
    microplate, the Fluoroskan Ascent FL. The IAsys Auto+ offers improved
    sensitivity, and the availability of prewritten scripts provides
    researchers with a high degree of flexibility when designing experiments.
    The Fluoroskan offers on-board dispensers for kinetic analysis, precise
    temperature control, orbital shaking, and robotic integration
    capabilities.

        The Company has focused its sales efforts on the research and
    clinical diagnostic markets, including chemical and pharmaceutical
    manufacturers, healthcare and hospital facilities, universities, medical
    and pharmaceutical research laboratories, veterinary and agricultural
    research laboratories, and government institutions. The Company's
    products are used principally by large clinical and research laboratories
    and manufacturers, including pharmaceutical companies, where large-batch,
    high-volume testing methods are required. 

        MALDI-TOF Mass Spectrometry. The Company currently offers three
    MALDI-TOF mass spectrometers, including an enhanced benchtop MALDI-TOF
    mass spectrometer that has significantly enhanced resolution, that was
    introduced in 1996. Mass spectrometry measures the molecular weight of a
    sample's components, thereby enabling identification and measurement of
    organic chemical compounds, inorganic elements, or both, contained in the
    sample.

        DNA Amplification. The Company designs, manufactures and markets PCR
    thermal cyclers, which amplify - or duplicate - deoxyribonucleic acid

                                        4PAGE
<PAGE>
    (DNA). PCR is used by research laboratories to diagnose and treat
    genetically based diseases, and in connection with drug discovery
    efforts. The technology automates various research procedures. The
    Company also manufactures hybridization ovens, which enable the
    identification of a DNA sequence.

        Capillary Electrophoresis. Capillary electrophoresis (CE) is a
    purification and separation technique commercially introduced in 1989. CE
    systems separate molecules as they move through an extremely narrow tube,
    or capillary, that is charged with an electric field. The Company's line
    of CE systems includes a low-cost, manually controlled CE system and a
    fully automated CE system with multiple wavelength detectors. In 1996,
    the Company introduced its new generation CE system that has more than
    twice the sample capacity of competing products, thereby permitting users
    to decrease labor costs by allowing longer periods of unattended
    operation. The Company's CE systems offer high sensitivity, as well as
    advanced data handling, control, and automation features. The Company
    also offers a line of CE capillaries, buffers, and other consumables.

        The largest market for CE systems and related supplies are
    pharmaceutical companies. One of the principal applications for CE
    systems is the analysis and separation of biomolecules such as proteins,
    peptides, and nucleic acids, including DNA. Applications of DNA
    separation by CE include the identification of specific individuals
    through DNA "fingerprinting" and the diagnosis of diseases and specific
    genetic disorders such as leukemia, hepatitis, and sickle cell anemia.

        Health Physics Instrumentation. The Company produces a broad range of
    products that, for worker safety and regulatory compliance, detect and
    measure nuclear radiation in and around nuclear power plants and other
    facilities where radioactive materials are used.

        Life sciences instrumentation revenues were $83,926,000, $47,425,000,
    and $22,534,000 in 1997, 1996, and 1995, respectively.

    Consumables

        The Company designs, manufactures, and markets laboratory
    consumables. The Company manufactures hand-held pipettes, used in
    delivering and handling liquid samples, as well as tips which, combined
    with pipettes, allows the precise delivery of samples throughout various
    processes. The Company also manufactures Microtiter(R) plates that are
    used in a variety of clinical immunodiagnostic procedures. In 1997, the
    Company launched its Cliniplate(TM) 384-well microplate, a new generation
    product that will address the high throughput sampling (HTS) marketplace.

        The Company distributes its consumables through regional and national
    distributor sales channels in over 100 countries worldwide.

         Consumables revenues were $30,513,000 in 1997 and $8,006,000 in
    1996.
                                        5PAGE
<PAGE>
    Information Management Systems

        The Company offers laboratory information management systems (LIMS)
    and chromatography data systems (CDS) for use in laboratories and
    clinical testing facilities. The Company's information management systems
    are designed to facilitate the monitoring and analysis of samples
    throughout the laboratory or clinical lifecycle.

        The Company designs, develops, and supports LIMS and CDS, and is
    recognized as one of the world's leading LIMS suppliers. The Company also
    maintains an implementation support group that provides software
    customization and project management services for its customers. A
    substantial majority of the Company's customers are Fortune 500 companies
    in the process chemical, aerospace, pharmaceutical, environmental, oil
    and gas, petrochemical, automotive, food and beverage, agricultural, and
    medical products industries. The Company's products are used primarily
    for research and development, quality assurance and quality control, and
    processing facilities.

        The Company's CDS products are open system analytical tools that
    assist users in analyzing chromatographic data obtained via gas and
    liquid chromatography and CE.

        The Company's LIMS and CDS products serve a variety of geographic
    markets. The Company maintains direct sales and service offices, as well
    as a network of distributors, in Australia, China, Europe, and the United
    States.

        Information management systems revenues were $25,015,000 in 1997 and
    $16,217,000 from March 29, 1996 (the date Thermo Instrument acquired the
    LIMS business as part of its acquisition of LSI) through December 28,
    1996.

        (ii) New Products
             ------------

        The Company's business includes the research and development of new
    products. (see "Principal Products and Services.")

        (iii) Raw Materials
              -------------

        Raw materials, components, and supplies purchased by the Company are
    either available from a number of different suppliers or from alternative
    sources that could be developed without a material adverse effect on the
    Company. To date, the Company has experienced no difficulties in
    obtaining these materials.

        (iv) Patents, Licenses, and Trademarks
             ---------------------------------

        The Company's policy is to protect its intellectual property rights
    and to apply for patent protection when appropriate. The Company
    currently holds several issued United States patents expiring at various
    dates ranging from 2002 to 2011. The Company also has applications
    pending for additional United States patents and a number of foreign
    counterparts for its patents in various foreign countries. In addition,

                                        6PAGE
<PAGE>
    the Company has registered, or other, trademarks. Patent protection
    provides the Company with competitive advantages with respect to certain
    systems. The Company believes, however, that technical know-how and trade
    secrets are more important to its business than patent protection.

        The Company seeks to maintain the confidentiality of its proprietary
    technology that is not covered by patent protection by requiring
    employees who work with proprietary information to sign confidentiality
    agreements and by limiting access by parties outside the Company to such
    confidential information. There can be no assurance, however, that these
    measures will prevent the unauthorized disclosure or use of this
    information, or that others will not be able to independently develop
    such information. Moreover, as is the case with the Company's patent
    rights, the enforcement by the Company of its trade secret rights can be
    lengthy and costly, with no guarantee of success.

        (v) Seasonal Influences
            -------------------

        There are no significant seasonal influences on the Company's sales
    of its products and services.

        (vi) Working Capital Requirements
             ----------------------------

        There are no special inventory requirements or credit terms extended
    to customers that would have a material adverse effect on the Company's
    working capital.

        (vii) Dependency on a Single Customer
              -------------------------------

        No single customer accounted for more than 10% of the Company's total
    revenues in any of the past three years.

        (viii) Backlog
               -------

        The backlog of firm orders was $20.7 million and $13.6 million as of
    January 3, 1998, and December 28, 1996, respectively. The Company
    believes that substantially all of its 1997 backlog will be completed
    during 1998. Certain of these orders are cancellable by the customer upon
    payment of a cancellation charge. 

        (ix) Government Contracts
             --------------------

        Less than 10% of the Company's total revenues in 1997 and 1996, and
    24% of the Company's total revenues in 1995, were derived from contracts
    or subcontracts with the federal government, which are subject to
    renegotiation of profits or termination. The Company does not have any
    knowledge of threatened or pending renegotiations or terminations.

        (x) Competition
            -----------

        The markets for the Company's products are highly competitive. In
    each of the markets it serves, the Company competes with a number of
    companies, many of which have greater engineering, manufacturing, and
    marketing resources than the Company.

                                        7PAGE
<PAGE>
    Life Sciences Instrumentation

        Molecular Interaction. The Company competes in the immunoassay market
    primarily on the basis of technological innovation, performance
    (including throughput and sensitivity), flexibility, and price. In the
    detection-systems market, the Company competes primarily with Bio-Tek
    Instruments, Inc., and Molecular Devices Corporation. In the
    automated-systems market, the Company's main competitors include Biacore
    International Inc., BioChem Pharma Inc., Immunosystems, Inc., Hamilton
    Bonaduz AG, and Tecan AG.

        MALDI-TOF Mass Spectrometry. The Company competes in the MALDI-TOF
    mass spectrometry market primarily on the basis of the technical
    performance of its MALDI-TOF mass spectrometers, as well as on the need
    in the analytical biochemistry community for highly automated mass
    spectrometers. To a lesser degree, the Company also competes on the basis
    of price. Principal competitors in the mass spectrometry market include
    PerSeptive Biosystems, Inc., a subsidiary of Perkin Elmer Corporation
    (Perkin Elmer); Shimadzu Corporation; Hewlett-Packard Company
    (Hewlett-Packard); Bruker Instruments Inc.; and Micromass Ltd.

        DNA Amplification. The Company's thermal cyclers compete in the DNA
    amplification market primarily on the basis of performance, ease of use,
    and, to a lesser extent, price. Major competitors include Perkin Elmer
    and MJ Research Technology, a division of Protean.

        Capillary Electrophoresis. The Company competes in the market for CE
    systems primarily on the basis of technical performance and automation
    features, and, to a lesser extent, price. The Company's principal
    competitors in the CE market include Beckman Instruments, Inc. (Beckman),
    Bio-Rad Laboratories, Inc., and Hewlett-Packard.

    Consumables

        The Company competes in the consumables market primarily on the basis
    of price, performance, and ease of use. The Company's principal
    competitors in the consumables or plastics market include Nalge Nunc
    Inc., Corning-Costar Corporation, Rainin Interments, Greiner GmbH, and
    Eppendorf GmbH.

    Information Management Systems

        The Company competes in the high-end LIMS and CDS markets primarily
    on the basis of the functionality, flexibility, and technical
    sophistication of its systems, as well as on its ability to tailor its
    software packages to a customer's specific laboratory protocols, its
    ability to provide superior customer service and technical support, and
    price. Significant competitors in the LIMS and CDS markets include Perkin
    Elmer, Beckman, Hewlett-Packard, the Laboratory MicroSystems, Inc.
    subsidiary of Instron Corporation, and Waters Instruments, Inc. 

                                        8PAGE
<PAGE>
        (xi) Research and Development
             ------------------------

        During 1997, 1996, and 1995, the Company expended approximately
    $11,670,000, $7,298,000, $1,325,000, respectively, on internally
    sponsored research and development programs.

        (xii) Environmental Protection Regulations
              ------------------------------------

        The Company believes that compliance by the Company with federal,
    state, and local environmental regulations will not have a material
    adverse effect on its capital expenditures, earnings, or competitive
    position. 

        (xiii) Number of Employees
               -------------------

        As of January 3, 1998, the Company had a total of 979 employees.

    (d) Financial Information about Exports by Domestic Operations and
        --------------------------------------------------------------
        About Foreign Operations
        ------------------------

        Financial information about exports by domestic operations and about
    foreign operations is summarized in Note 8 to Consolidated Financial
    Statements in the Company's 1997 Annual Report to Shareholders, which
    information is incorporated herein by reference.

    (e) Executive Officers of the Registrant
        ------------------------------------

                                  Present Title (Year First Became Executive
        Name                 Age  Officer)
        -------------------  ---  ------------------------------------------
        Colin Maddix         52   Chief Executive Officer and President
                                    (1998)
        Donald W. Hanna      41   Vice President (1995)
        John N. Hatsopoulos  63   Chief Financial Officer and Senior Vice
                                    President (1995)
        Paul F. Kelleher     55   Chief Accounting Officer (1995)

        Each executive officer serves until his successor is chosen or
    appointed by the Board of Directors and qualified or until earlier
    resignation, death, or removal. Messrs. Hatsopoulos and Kelleher have
    held comparable positions for at least five years with Thermo Instrument
    and Thermo Electron. Mr. Maddix has been Chief Executive Officer,
    President, and a Director of the Company since March 1998. Since 1992,
    Mr. Maddix has been President and Chief Executive Officer of the Clinical
    Products Group of LSI, which includes Shandon Inc. and ALKO Diagnostics
    Corporation, and which supplies reagents, equipment, and consumables to
    histology-cytology and pathology laboratories worldwide. Mr. Hanna has
    been Vice President of the Company since its inception in February 1995,
    and has been President of the Company's Eberline subsidiary since 1994.
    Prior to joining the Company, Mr. Hanna was President of Thermo
    Instrument's National Nuclear Corporation subsidiary, a manufacturer of
    products for the nuclear power industry, from 1990 through 1994. Messrs.
    Hatsopoulos and Kelleher are full-time employees of Thermo Electron, but

                                        9PAGE
<PAGE>
    devote such time to the affairs of the Company as the Company's needs
    reasonably require.

    Item 2. Properties
            ----------

        The Company owns approximately 70,000 square feet of manufacturing,
    sales, and administration space in New Mexico, and 2,000 square feet of
    office space in Stockholm, Sweden. The Company leases 67,000 square feet
    of manufacturing, sales, and administration space in Virginia,
    Massachusetts, and California, including 14,000 square feet subleased
    from ThermoQuest, under leases expiring through 2002. The Company leases
    302,000 square feet of manufacturing, sales, and administration space in
    Finland, England, Russia, and other European countries, under leases
    expiring from 1999 through 2016. In addition, the Company leases 12,000
    square feet of sales space in Japan and Hong Kong under leases expiring
    from 1998 through 1999. The Company believes that its facilities are in
    good condition and are suitable and adequate to meet current needs. With
    respect to leases expiring in the near future, in the event that the
    Company does not renew such leases, the Company believes that suitable
    alternative space is available for lease on acceptable terms.












                                       10PAGE
<PAGE>
                                     PART II

    Item 3. Legal Proceedings
            -----------------

        Not applicable.

    Item 4. Submission of Matters to a Vote of Security Holders
            ---------------------------------------------------

         Not applicable.

    Item 5. Market for Registrant's Common Equity and Related Stockholder
            -------------------------------------------------------------
            Matters
            -------

        Information concerning the market and market price for the
    Registrant's common stock, $.01 par value, and dividend policy is
    included under the sections labeled "Common Stock Market Information" and
    "Dividend Policy" in the Registrant's 1997 Annual Report to Shareholders
    and is incorporated herein by reference.

    Item 6. Selected Financial Data
            -----------------------

        The information required under this item is included under the
    sections labeled "Selected Financial Information" and "Dividend Policy"
    in the Registrant's 1997 Annual Report to Shareholders and is
    incorporated herein by reference.

    Item 7. Management's Discussion and Analysis of Financial Condition and
            ---------------------------------------------------------------
            Results of Operations
            ---------------------

        The information required under this item is included under the
    heading "Management's Discussion and Analysis of Financial Condition and
    Results of Operations" in the Registrant's 1997 Annual Report to
    Shareholders and is incorporated herein by reference.

    Item 8. Financial Statements and Supplementary Data
            -------------------------------------------

        The Registrant's Consolidated Financial Statements and Supplementary
    Data are included in the Registrant's 1997 Annual Report to Shareholders
    and are incorporated herein by reference.

    Item 9. Changes in and Disagreements with Accountants on Accounting and
            ---------------------------------------------------------------
            Financial Disclosures
            ---------------------

        Not applicable.


                                       11PAGE
<PAGE>
                                    PART III

    Item 10. Directors and Executive Officers of the Registrant
             --------------------------------------------------

        The information concerning directors required under this item is
    incorporated herein by reference from the material contained under the
    caption "Election of Directors" in the Registrant's definitive proxy
    statement to be filed with the Securities and Exchange Commission
    pursuant to Regulation 14A, not later than 120 days after the close of
    the fiscal year. The information concerning delinquent filers pursuant to
    Item 405 of Regulation S-K is incorporated herein by reference from the
    material contained under the heading "Section 16(a) Beneficial Ownership
    Reporting Compliance" under the caption "Stock Ownership" in the
    Registrant's definitive proxy statement to be filed with the Securities
    and Exchange Commission pursuant to Regulation 14A, not later than 120
    days after the close of the fiscal year.

    Item 11. Executive Compensation
             ----------------------

        The information required under this item is incorporated herein by
    reference from the material contained under the caption "Executive
    Compensation" in the Registrant's definitive proxy statement to be filed
    with the Securities and Exchange Commission pursuant to Regulation 14A,
    not later than 120 days after the close of the fiscal year.

    Item 12. Security Ownership of Certain Beneficial Owners and Management
             --------------------------------------------------------------

        The information required under this item is incorporated herein by
    reference from the material contained under the caption "Stock Ownership"
    in the Registrant's definitive proxy statement to be filed with the
    Securities and Exchange Commission pursuant to Regulation 14A, not later
    than 120 days after the close of the fiscal year.

    Item 13. Certain Relationships and Related Transactions
             ----------------------------------------------

        The information required under this item is incorporated herein by
    reference from the material contained under the caption "Relationship
    with Affiliates" in the Registrant's definitive proxy statement to be
    filed with the Securities and Exchange Commission pursuant to Regulation
    14A, not later than 120 days after the close of the fiscal year.






                                       12PAGE
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                                     PART IV

    Item 14. Exhibits, Financial Statement Schedules, and Reports on Form 8-K
             ----------------------------------------------------------------

       (a,d) Financial Statements and Schedules
             ----------------------------------

             (1) The consolidated financial statements set forth in the list
                 below are filed as part of this Report.

             (2) The consolidated financial statement schedule set forth in
                 the list below is filed as part of this Report.

             (3) Exhibits filed herewith or incorporated herein by reference
                 are set forth in Item 14(c) below.

             List of Financial Statements and Schedules Referenced in this
             -------------------------------------------------------------
             Item 14
             -------

             Information incorporated by reference from Exhibit 13 filed
             herewith:

                 Consolidated Statement of Operations
                 Consolidated Balance Sheet
                 Consolidated Statement of Cash Flows
                 Consolidated Statement of Shareholders' Investment
                 Notes to Consolidated Financial Statements
                 Report of Independent Public Accountants

             Financial Statement Schedules filed herewith:

                 Schedule II: Valuation and Qualifying Accounts

             All other schedules are omitted because they are not applicable
             or not required, or because the required information is shown
             either in the financial statements or in the notes thereto.

         (b) Reports on Form 8-K
             -------------------

             None.

         (c) Exhibits
             --------

             See Exhibit Index on the page immediately preceding exhibits.




                                       13PAGE
<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.

    Date: March 19, 1998              THERMO BIOANALYSIS CORPORATION


                                      By:Colin Maddix
                                         -----------------------------
                                         Colin Maddix
                                         President and Chief Executive
                                           Officer

        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 indicated, as of March 19, 1998.

    Signature                     Title
    ---------                     -----
    By: Colin Maddix              President, Chief Executive Officer,
        -----------------------
        Colin Maddix                    and Director

    By: John N. Hatsopoulos       Chief Financial Officer and Senior
        ------------------------
        John N. Hatsopoulos             Vice President

    By: Paul F. Kelleher          Chief Accounting Officer
        ------------------------
        Paul F. Kelleher

    By: Earl R. Lewis             Chairman of the Board and Director
        ------------------------
        Earl R. Lewis

    By: Elias P. Gyftopoulos      Director
        ------------------------
        Elias P. Gyftopoulos

    By: Barry S. Howe             Director
        ------------------------
        Barry S. Howe

    By: Jonathan W. Painter       Director
        ------------------------
        Jonathan W. Painter

    By: Arvin H. Smith            Director
        ------------------------
        Arvin H. Smith

    By: Arnold N. Weinberg        Director
        ------------------------
        Arnold N. Weinberg

                                       14PAGE
<PAGE>
                    Report of Independent Public Accountants
                    ----------------------------------------

    To the Shareholders and Board of Directors of Thermo BioAnalysis
    Corporation:

        We have audited, in accordance with generally accepted auditing
    standards, the consolidated financial statements included in Thermo
    BioAnalysis Corporation's Annual Report to Shareholders incorporated by
    reference in this Form 10-K, and have issued our report thereon dated
    February 17, 1998. Our audits were made for the purpose of forming an
    opinion on those statements taken as a whole. The schedule listed in Item
    14 on page 13 is the responsibility of the company's management and is
    presented for purposes of complying with the Securities and Exchange
    Commission's rules and is not part of the basic consolidated financial
    statements. The schedule has been subjected to the auditing procedures
    applied in the audits of the basic consolidated financial statements and,
    in our opinion, fairly states in all material respects the consolidated
    financial data required to be set forth therein in relation to the basic
    consolidated financial statements taken as a whole.



                                                Arthur Andersen LLP



    Boston, Massachusetts
    February 17, 1998









                                       15PAGE
<PAGE>
  SCHEDULE II


                         THERMO BIOANALYSIS CORPORATION
                        Valuation and Qualifying Accounts
                                 (In thousands)


                    Balance             Provision                            
                         at               Charged  Accounts            Balance
                  Beginning   Accounts         to   Written             at End
  Description       of Year  Recovered    Expense       Off  Other(a)  of Year
  ----------------------------------------------------------------------------
  Allowance for
   Doubtful Accounts

  Year Ended
   January 3, 1998    $ 991      $   -      $ 528     $(232)   $3,798   $5,085

  Year Ended
   December 28, 1996  $ 154      $   9      $ 210     $(188)   $  806   $  991

  Year Ended
   December 30, 1995  $ 154      $   -      $   2     $  (2)   $    -   $  154

  (a) Allowances of businesses acquired during the year as described in Note
      2 to Consolidated Financial Statements in the Registrant's 1997 Annual
      Report to Shareholders and the effect of foreign currency translation.








                                       16PAGE
<PAGE>
                                  EXHIBIT INDEX

    Exhibit
    Number      Description of Exhibit
    ------------------------------------------------------------------------
      2.1*      Purchase Agreement dated as of February 5, 1996, by and
                among the Company, Dynatech Corporation, and certain of
                their respective affiliates. 

      2.2       Share Purchase Agreement dated as of May 6, 1997, between
                the Company and Thermo Instrument Systems Inc., with respect
                to Labsystems OY and Hybaid Limited (incorporated by
                reference herein from Exhibit 2 to the Company's Quarterly
                Report on Form 10-Q for the quarter ended March 29, 1997
                [File No. 1-12179]).

      2.3       Share Purchase Agreement dated as of July 30, 1997, between
                the Company and Thermo Instrument Systems Inc., with respect
                to Labsystems Japan (incorporated by reference herein from
                Exhibit 2 to the Company's Quarterly Report on Form 10-Q for
                the quarter ended June 28, 1997 [File No. 1-12179]).

      3.1*      Certificate of Incorporation of the Company.

      3.2*      By-Laws of the Company.
      4*        Form of Common Stock Certificate.

     10.1*      Corporate Services Agreement dated as of February 27, 1995,
                between Thermo Electron and the Company.

     10.2       Thermo Electron Corporate Charter, as amended and restated
                effective January 3, 1993 (incorporated by reference herein
                from Exhibit 10.1 to Thermo Electron's Annual Report on Form
                10-K for the fiscal year ended January 2, 1993 [File No.
                1-8002]).

     10.3*      Tax Allocation Agreement dated as of February 27, 1995,
                between Thermo Electron and the Company.

     10.4       Amended and Restated Master Repurchase Agreement dated as of
                December 28, 1996, between Thermo Electron and the Company
                (incorporated by reference herein from Exhibit 10.4 to the
                Company's Annual Report on Form 10-K for the fiscal year
                ended December 28, 1996 [File No. 1-12179]).

     10.5       Amended and Restated Master Guarantee Reimbursement and Loan
                Agreement dated as of December 2, 1997, between Thermo
                Electron and the Company (incorporated by reference herein
                from Exhibit 10.39 to Thermo Instrument's Annual Report on
                Form 10-K for the fiscal year ended January 3, 1998 [File
                No. 1-9786]).

                                       17PAGE
<PAGE>
                                  EXHIBIT INDEX

    Exhibit
    Number      Description of Exhibit
    ------------------------------------------------------------------------
     10.6       Amended and Restated Master Guarantee Reimbursement and Loan
                Agreement dated as of December 2, 1997, between Thermo
                Instrument and the Company.

     10.7*      Equity Incentive Plan of the Company.

                In addition to the stock-based compensation plans of the
                Company, the executive officers of the Company may be
                granted awards under stock-based compensation plans of
                Thermo Electron and Thermo Instrument for services rendered
                to the Company or such affiliated corporations. The terms of
                such plans are substantially the same as those of the
                Company's Equity Incentive Plan.

     10.8*      Deferred Compensation Plan for Directors of the Company.
     10.9*      Directors' Stock Option Plan of the Company.

     10.10*     Form of Indemnification Agreement for Officers and
                Directors.

     10.11*     Asset Transfer Agreement dated as of February 27, 1995,
                between Thermo Instrument and the Company.

     10.12*     Asset Transfer Agreement dated as of February 27, 1995,
                between Thermo Separation Products Inc. and the Company.

     10.13*     Exclusive License Agreement dated as of February 27, 1995,
                between Thermo Separation Products Inc. and the Company.

     10.14*     Exclusive License Agreement dated as of February 27, 1995,
                between the Company and Thermo Separation Products Inc.

     10.15*     Manufacturing Agreement dated as of February 27, 1995,
                between Thermo Separation Products Inc. and the Company.

     10.16*     Note Purchase Agreement dated as of July 22, 1996, between
                Thermo Instrument and the Company.

     10.17*     $50,000,000 Principal Amount 4.875% Convertible Subordinated
                Note due 2001 dated July 22, 1996.

     10.18*     Asset and Share Purchase Agreement dated as of July 22,
                1996, among SID Instruments Inc., HB Instruments Inc., the
                Company, and Thermo Instrument.

     10.19*     Asset Purchase Agreement dated as of July 22, 1996, among
                Thermo LabSystems Limited, FI Instruments Inc., Thermo FAST
                U.K. Limited, the Company, and Thermo Instrument.

                                       18PAGE
<PAGE>
                                  EXHIBIT INDEX

    Exhibit
    Number      Description of Exhibit
    ------------------------------------------------------------------------
     10.20      Restated Stock Holding Assistance Plan and Form of
                Promissory Note (incorporated by reference herein from
                Exhibit 10.20 to the Company's Annual Report on Form 10-K
                for the fiscal year ended December 28, 1996 [File No.
                1-12179]).

     13         Annual Report to Shareholders for the year ended January 3,
                1998 (only those portions incorporated herein by reference).

     21         Subsidiaries of the Registrant.

     27.1       Financial Data Schedule for the year ended January 3, 1998.

     27.2       Financial Data Schedule for the quarter ended March 29, 1997
                (restated for the adoption of SFAS No. 128).

     27.3       Financial Data Schedule for the quarter ended September 27,
                1997 (restated for the adoption of SFAS No. 128).


    Each exhibit above which is marked with an asterisk (*) is incorporated
    by reference to the correspondingly numbered exhibit to the Company's
    Registration Statement on Form S-1 [File No. 333-8697].