CENTRAL BANCORP, INC.

                                 CODE OF ETHICS
                                       FOR
                     SENIOR EXECUTIVE AND FINANCIAL OFFICERS


GENERAL PHILOSOPHY

     The  honesty,  integrity  and sound  judgment of our senior  executive  and
financial officers is essential to Central Bancorp's reputation and success.

     This Code of Ethics governs the actions and working relationships of senior
executive and financial  officers of Central Bancorp,  Inc. and its subsidiaries
and  affiliates  (collectively,  "Central  Bancorp")  with current and potential
customers,   consumers,   fellow   employees,   competitors,    government   and
self-regulatory  organizations,  the media,  and anyone  else with whom  Central
Bancorp has contact.  These relationships are essential to the continued success
of Central Bancorp as a financial services provider.

     This Code of Ethics:

     -    Requires  the  highest  standards  for  honest  and  ethical  conduct,
          including  proper and ethical  procedures  for dealing  with actual or
          apparent  conflicts  of interest  between  personal  and  professional
          relationships.

     -    Requires full, fair, accurate, timely and understandable disclosure in
          the  periodic  reports  required to be filed by Central  Bancorp  with
          governmental and regulatory agencies.

     -    Requires compliance with applicable laws, rules and regulations.

     -    Addresses  potential  or apparent  conflicts  of interest and provides
          guidance for senior  executive and financial  officers to  communicate
          those conflicts to Central Bancorp.

     -    Addresses  misuse or  misapplication  of Central Bancorp  property and
          corporate opportunities.

     -    Requires the highest level of confidentiality  and fair dealing within
          and outside the Central Bancorp environment.

     -    Requires reporting of any illegal behavior.


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IDENTIFICATION OF SENIOR EXECUTIVE AND FINANCIAL OFFICERS

     For purposes of this Code of Ethics, Central Bancorp's senior executive and
financial  officers  shall consist of all officers with the title of Senior Vice
President or higher, as well as Central Bank's Vice President and Controller.


CONFLICTS OF INTEREST

     A "conflict of interest"  occurs when your private  interest  interferes or
appears to interfere in any way with the interests of Central  Bancorp.  You are
expected to avoid all situations that might lead to a real or apparent  material
conflict between your  self-interest and your duties and  responsibilities  as a
senior  executive  or  financial  officer of Central  Bancorp.  Any  position or
interest,  financial or  otherwise,  which could  materially  conflict with your
performance as a senior executive or financial  officer of Central  Bancorp,  or
which  affects or could  reasonably be expected to affect your  independence  or
judgment  concerning   transactions  between  Central  Bancorp,  its  customers,
suppliers or competitors  or otherwise  reflects  negatively on Central  Bancorp
would be considered a conflict of interest.


CONFIDENTIALITY

     Nonpublic   information   regarding  Central  Bancorp  or  its  businesses,
employees,  customers and suppliers is confidential. As a Central Bancorp senior
executive or financial officer,  you are trusted with confidential  information.
You are only to use  such  confidential  information  for the  business  purpose
intended.  You are not to share confidential  information with anyone outside of
Central Bancorp,  including  family and friends,  or with other employees who do
not need the information to carry out their duties.  You may be required to sign
a confidentiality agreement in the course of your employment at Central Bancorp.
You remain under an obligation to keep all information confidential even if your
employment with Central Bancorp ends.

     The following is a non-exclusive list of confidential information:

     (i)  Trade  secrets,  which include any business or technical  information,
          such  as  formula,   program,   method,   technique,   compilation  or
          information that is valuable because it is not generally known.

     (ii) All rights to any invention or process  developed by an employee using
          Central Bancorp facilities or trade secret information,  from any work
          for Central Bancorp,  or relating to Central  Bancorp's  business,  is
          considered to be  "work-for-hire"  under the United  States  copyright
          laws and shall belong to Central Bancorp.

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     (iii)Proprietary   information   such  as  customer  lists  and  customers'
          confidential information.

     Public and media communications involving Central Bancorp must be made only
by Central Bancorp's Chief Executive Officer or his designee.


CORPORATE OPPORTUNITIES

     Using  confidential  information  about Central  Bancorp or its businesses,
directors,  officers, employees,  customers, consumers or suppliers for personal
benefit or disclosing  such  information to others outside your normal duties is
prohibited.

     Title 18 U.S.  Code,  Section  215,  makes it a  criminal  offense  for any
Central Bancorp employee to corruptly:

     (i)  solicit for himself or herself or for a third party  anything of value
          from  anyone in  return  for any  business,  service  or  confidential
          information of Central Bancorp ; or

     (ii) accept anything of value (other than normal  authorized  compensation)
          from anyone in connection with the business of Central Bancorp, either
          before or after a transaction is discussed or consummated.

     Senior executive and financial officers are prohibited from:

     (i)  Personally  benefiting from  opportunities that are discovered through
          the  use  of  Central  Bancorp  property,  contacts,   information  or
          position.

     (ii) Accepting  employment or engaging in a business (including  consulting
          or similar  arrangements)  that may conflict with the  performance  of
          your duties or Central Bancorp's interest.

     (iii)Soliciting,  demanding,  accepting  or agreeing to accept  anything of
          value  from any person in  conjunction  with the  performance  of your
          employment or duties at Central Bancorp.

     (iv) Acting on behalf of Central Bancorp in any transaction in which you or
          your immediate family has a significant  direct or indirect  financial
          or other interest.

     There are  certain  situations  in which you may accept a personal  benefit
from someone with whom you transact business such as:

     (i)  Accepting  a gift in  recognition  of a commonly  recognized  event or
          occasion  (such  as a  promotion,  new  job,  wedding,  retirement  or
          holiday).


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          An award in  recognition  of service  and  accomplishment  may also be
          accepted  without  violating these guidelines so long as the gift does
          not exceed $100 from any one individual in any calendar year.

     (ii) Accepting  something  of  value if the  benefit  is  available  to the
          general  public under the same  conditions on which it is available to
          you.

     (iii)Accepting meals, refreshments,  travel arrangements and accommodations
          and  entertainment  of reasonable  value in the course of a meeting or
          other occasion to conduct business or foster business relations if the
          expense would be reimbursed by Central  Bancorp as a business  expense
          if the other party did not pay for it.


INSIDER TRADING

     It is  both  unethical  and  illegal  to  buy,  sell,  trade  or  otherwise
participate  in  transactions  involving  Central  Bancorp common stock or other
security while in possession of material information  concerning Central Bancorp
that has not been  released to the general  public,  but which when released may
have an impact on the market price of the Central  Bancorp common stock or other
equity  security.  It is also  unethical  and  illegal  to buy,  sell,  trade or
otherwise  participate  in  transactions  involving  the  common  stock or other
security of any other company while in possession of similar non-public material
information concerning such company. Senior executive and financial officers are
advised that they are required to comply with the Central Bancorp,  Inc. Insider
Trading Policy and the Central  Bancorp,  Inc.  Special  Trading  Procedures for
Directors,  Officers and Certain Employees with Access to Sensitive Information.
Any questions  concerning the propriety of participating in a Central Bancorp or
other  company  stock or other  security  transaction  should be directed to the
Chief Financial Officer at (617) 629-4244.  Copies of the Insider Trading Policy
and the Special  Trading  Procedures are available from Central  Bancorp's Chief
Financial Officer.


EXTENSIONS OF CREDIT

     Central  Bancorp's  subsidiary  bank  may  extend  credit  to any  officer,
director,  or  principal  shareholder  or  employee of Central  Bancorp  only in
compliance with Massachusetts and federal law and regulations and Central Bank's
policy on Loans to Principal  Shareholders,  Directors,  Officers and  Employees
(the  "Loan  Policy").  A copy of the Loan  Policy  is  available  from  Central
Bancorp's Chief Financial Officer.


OUTSIDE BUSINESS RELATIONSHIPS

     Senior   executive  and  financial   officers   should   disclose  all  new
directorships  or  potential  directorships  to the  Chairman  of the  Board  of
Directors  in order to avoid any

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conflicts  of  interest.  Senior  executive  and  financial  officers of Central
Bancorp are prohibited from holding outside employment.

     Central Bancorp  encourages  civic,  charitable,  educational and political
activities as long as they do not interfere with the  performance of your duties
at Central Bancorp.


FAIR DEALING

     Each senior executive and financial officer should undertake to deal fairly
with  Central  Bancorp's  customers,   suppliers,   competitors  and  employees.
Additionally,  no one should take  advantage  of another  through  manipulation,
concealment,  abuse of  privileged  information,  misrepresentation  of material
facts, or any other unfair-dealing practices.

     Senior executive and financial  officers must disclose prior to or at their
time  of  hire  the  existence  of  any  employment  agreement,  non-compete  or
non-solicitation agreement,  confidentiality agreement or similar agreement with
a former  employer that would in any way restrict or prohibit the performance of
any duties or responsibilities  of their positions with Central Bancorp.  Copies
of such  agreements  should be provided to the Vice President of Human Resources
to permit evaluation of the agreement in light of the employee's position. In no
event shall an employee use any trade secrets,  proprietary information or other
similar  property,  acquired in the course of his or her employment with another
employer,  in the  performance  if his or her duties for or on behalf of Central
Bancorp.

     Senior  executive and financial  officers should not directly or indirectly
accept  bequests  under a will or trust if such  bequests have been made to them
because of their employment with Central Bancorp.


PROTECTION AND PROPER USE OF CENTRAL BANCORP PROPERTY

     All senior  executive and financial  officers and employees  should protect
Central Bancorp's property and assets and ensure their efficient and proper use.
Theft,   carelessness   and  waste  can  directly   impact   Central   Bancorp's
profitability,  reputation  and success.  Permitting  Central  Bancorp  property
(including data transmitted or stored  electronically and computer resources) to
be damaged,  lost,  or used in an  unauthorized  manner is strictly  prohibited.
Senior  executive and financial  officers may not use  corporate,  bank or other
official stationery for personal purposes.


COMPLIANCE WITH LAWS, RULES AND REGULATIONS

     This  Code of  Ethics  is  based  on  Central  Bancorp's  policy  that  all
directors,  officers and employees comply with the law. While the law prescribes
a minimum

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standard of conduct, this Code of Ethics requires conduct that often exceeds the
legal standard.


PREPARATION OF PERIODIC REPORTS FILED WITH GOVERNMENTAL AND REGULATORY AGENCIES

     Particular care is required in the preparation of Central Bancorp's filings
("Securities  Reports")  with the  Securities  and Exchange  Commission  ("SEC")
pursuant the Securities Act of 1933, as amended and the Securities  Exchange Act
of  1934,  as  amended  and the  rules  and  regulations  of the SEC  thereunder
(collectively,  the "Securities Laws"), as well as Central Bancorp's filings and
communications   (collectively,   "Regulatory   Reports")   with   federal   and
Massachusetts  bank  regulatory  authorities.   It  is  essential  that  Central
Bancorp's   Securities  Reports  contain  full,  fair,   accurate,   timely  and
understandable disclosure and otherwise comply with the letter and spirit of the
Securities Laws for the protection of Central Bancorp and its  stockholders  and
to engender public confidence in the information  provided by Central Bancorp in
its  Securities  Reports.  Similarly,  it is essential  that  Central  Bancorp's
Regulatory  Reports  contain full,  fair,  accurate,  timely and  understandable
disclosure and otherwise comply with the letter and spirit of applicable federal
and state banking laws and regulations ("Banking Laws"). Accordingly, the senior
executive and financial  officers of Central Bancorp must use their best efforts
to ensure that Central Bancorp's  Securities  Reports and Regulatory Reports and
other  public  communications  made  by  Central  Bancorp  contain  full,  fair,
accurate,  timely and understandable  disclosure and that Central Bancorp at all
times  complies  in all  material  respects  with the  letter  and spirit of the
Securities Laws and the Banking Laws.


REPORTING OF ILLEGAL OR UNETHICAL BEHAVIOR AND VIOLATIONS OF THIS CODE OF ETHICS

     All senior executive and financial officers are expected to demonstrate the
ability to properly manage their personal finances, particularly the prudent use
of credit.  Central  Bancorp  recognizes  that its customers must have faith and
confidence  in the honesty and  character of its senior  executive and financial
officers.  In addition to the  importance of  maintaining  customer  confidence,
there are  specific  laws that  outline the actions  Central  Bancorp  must take
regarding  any known,  or  suspected,  crime  involving  the  affairs of Central
Bancorp.  With regard to financial affairs, a bank must make a criminal referral
in the case of any known, or suspected,  theft,  embezzlement,  check/debit card
fraud, kiting,  misapplication or other defalcation involving bank funds or bank
personnel in any amount.

     Fraud  is  an  element  of  business  that  can  significantly  affect  the
reputation and success of Central  Bancorp.  Central Bancorp requires its senior
executive  and  financial  officers  to  talk to the  Vice  President  of  Human
Resources,  reporting directly to the Audit Committee of the Board of Directors,
to report and discuss any known or suspected


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criminal  activity  involving  Central Bancorp or its employees.  If, during the
course of employment,  you become aware of any  suspicious  activity or behavior
including concerns regarding  questionable  accounting or auditing matters,  you
must report violations of laws, rules, regulations or this Code of Ethics to the
Vice President of Human Resources,  reporting directly to the Audit Committee of
the  Board  of  Directors.  Reporting  the  activity  will  not  subject  you to
discipline absent a knowingly false report.


ADMINISTRATION AND WAIVER OF CODE OF ETHICS

     This Code of Ethics  shall be  administered  and  monitored  by the Central
Bancorp  Vice  President  of Human  Resources,  reporting  directly to the Audit
Committee of the Board of Directors.  Any questions and further  information  on
this Code of Ethics should be directed to this individual.

     It is also the  responsibility  of the Vice President of Human Resources to
annually  reaffirm  compliance with this Code of Ethics by all senior  executive
and  financial  officers,  and to obtain a signed  certificate  that each senior
executive and financial officer has read and understands the guidelines and will
comply with them.  Senior  executive and financial  officers will be required to
sign a receipt  form  indicating  they  have  read this Code of Ethics  and will
comply with its provisions.

     Senior executive and financial  officers of Central Bancorp are expected to
follow this Code of Ethics at all times.  Generally,  there should be no waivers
to this Code of Ethics.  However, in rare circumstances conflicts may arise that
necessitate  waivers.  Waivers will be determined on a case-by-case basis by the
Audit  Committee of the Board of Directors.  The Audit Committee of the Board of
Directors  shall have the sole and absolute  discretionary  authority to approve
any deviation or waiver from this Code of Ethics. Any waiver and the grounds for
such waiver by directors or executive  officers  shall be promptly  disclosed to
stockholders in a Current Report on Form 8-K.

     Known or suspected  violations of this Code of Ethics will be  investigated
and may result in disciplinary action up to and including immediate  termination
of employment.

     Central Bancorp will provide to any person without charge,  upon request, a
copy of this Code of  Ethics.  Such  request  should be made,  in  writing,  to:
Corporate Secretary,  Central Bancorp, Inc., 399 Highland Avenue, Somerville, MA
02144.

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