<PAGE>

                                                                     Exhibit 3.3
                                    Certified to be a true and correct copy
                                    of the By-laws of the Corporation, as
                                    amended through September 21, 1999.


                                    /s/ Timothy R. Parry
                                    --------------------------------------------
                                    Timothy R. Parry, Secretary


                      HEALTH MANAGEMENT ASSOCIATES, INC.

                                    BY-LAWS


                                   Article I

                                    Offices

     Section 1.  The registered office shall be in the City of Wilmington,
     ----------
County of New Castle, State of Delaware.

     Section 2.  The corporation may also have offices at such other places both
     ----------
within and without the State of Delaware as the board of directors may from time
to time determine or the business of the corporation may require.

                                   Article II

                            Meeting of Stockholders

     Section 1.  Except as otherwise provided in the certificate of
     ----------
incorporation, meetings of the stockholders for the election of directors shall
be held in the City of Fort Myers, Florida, at such place as may be fixed from
time to time by the board of directors, or at such other place either within or
without the State of Delaware as shall be designated from time to time by the
board of directors and stated in the notice of the meeting.

     Section 2.  Annual meetings of stockholders, commencing with the year 1980,
     ----------
shall be held on the first Wednesday of February if not a legal holiday, and if
a holiday, then on the next secular day following or as shall be designated from
time to time by the board of directors and stated in the notice of the meeting,
at which they shall elect by a plurality vote a board of directors (except as
otherwise provided in the certificate of incorporation), and transact such other
business as may properly be brought before the meeting.
<PAGE>

     Section 3.  Written notice of the annual meeting stating the place, date
     ----------
and hour of the meeting shall be given to each stockholder entitled to vote at
such meeting not less than ten or more than sixty days before the date of the
meeting.

     Section 4.  The officer who has charge of the stock ledger of the
     ----------
corporation shall prepare and make, at least ten days before every meeting of
stockholders, a complete list of the stockholders entitled to vote at the
meeting, arranged in alphabetical order, and showing the address of each
stockholder and the number of shares registered in the name of each stockholder.
Such list shall be open to the examination of any stockholder, for any purpose
germane to the meeting, during ordinary business hours, for a period of at least
ten days prior to the meeting, either at a place within the city where the
meeting is to be held, which place shall be specified in the notice of the
meeting, or, if not so specified, at the place where the meeting is to be held.
The list shall also be produced and kept at the time and place of the meeting
during the whole time thereof, and may be inspected by any stockholder who is
present.

     Section 5.  Special meetings of the stockholders, for any purpose or
     ----------
purposes, unless otherwise prescribed by statute or by the certificate of
incorporation, may be called by the chief executive officer and shall be called
by the chief executive officer or secretary at the request in writing of a
majority of the board of directors, or at the request in writing of stockholders
owning a majority in amount of the entire capital stock of the corporation
issued and outstanding and entitled to vote. Such request shall state the
purpose or purposes of the proposed meeting.

     Section 6.  Written notice of a special meeting stating the place, date and
     ----------
hour of the meeting and the purpose or purposes for which the meeting is called,
shall be given not less than ten or nor more than sixty days before the date of
the meeting, to each stockholder entitled to vote at such meeting.

     Section 7.  Business transacted at any special meeting of stockholders
     ----------
shall be limited to the purposes stated in the notice.

     Section 8.  The holders of a majority of the stock issued and outstanding
     ----------
and entitled to vote thereat, present in person or represented by proxy, shall
constitute a quorum at all meetings of the stockholders for the transaction of
business except as otherwise provided by statute or by the certificate of
incorporation.  If, however, such quorum shall not be present or represented at
any meeting of the stockholders, the stockholders entitled to vote thereat,
present in person or represented by proxy, shall have power to adjourn the
meeting from time to time, without notice other than announcement at the
meeting, until a quorum shall be present or represented.  At such adjourned
meeting at which a quorum
<PAGE>

shall be present or represented any business may be transacted which might have
been transacted at the meeting as originally notified. If the adjournment is for
more than thirty days, or if after the adjournment a new record date is fixed
for the adjourned meeting, a notice of the adjourned meeting shall be given to
each stockholder of record entitled to vote at the meeting.

     Section 9.  When a quorum is present at any meeting, the vote of the
     ----------
holders of a majority of the stock having voting power present in person or
represented by proxy shall decide any question brought before such meeting,
unless the question is one upon which by express provision of the statutes or of
the certificate of incorporation, a different vote is required in which case
such express provision shall govern and control the decision of such question.

     Section 10. Unless otherwise provided in the certificate of incorporation
     -----------
each stockholder shall at every meeting of the stockholders be entitled to one
vote in person or by proxy for each share of the capital stock having voting
power held by such stockholder, but no proxy shall be voted on after three years
from its date, unless the proxy provides for a longer period.

     Section 11. Unless otherwise provided in the certificate of incorporation,
     -----------
any action required to be taken at any annual or special meeting of stockholders
of the corporation, or any action which may be taken at any annual or special
meeting of such stockholders, may be taken without a meeting, without prior
notice and without a vote, if a consent in writing, setting forth the action so
taken, shall be signed by the holders of outstanding stock having not less than
the minimum number of votes that would be necessary to authorize or take such
action at a meeting at which all shares entitled to vote thereon were present
and voted.  Prompt notice of the taking of the corporate action without a
meeting by less than unanimous written consent shall be given to those
stockholders who have not consented in writing.

                                  Article III

                                   Directors

     Section 1.  Except as otherwise provided in the certification of
     ----------
incorporation, the number of directors which shall constitute the whole board
shall be not less than five nor more than nine, and, within such limits, the
number of directors shall be determined by resolution of the board of directors
or by the stockholders at the annual meeting.  The directors shall be elected at
the annual meeting of the stockholders, except as provided in Section 2 of this
Article and except as provided in the certificate of incorporation, and each
director elected shall hold office until his successor is elected and qualified.
Directors need not be stockholders.
<PAGE>

     Section 2.  Except as otherwise provided in the certificate of
     ----------
incorporation, vacancies and newly created directorships resulting from any
increase in the authorized number of directors may be filled by a majority of
the directors then in office, though less than a quorum, or by a sole remaining
director, and the directors so chosen shall hold office until the next annual
election and until their successors are duly elected and shall qualify, unless
sooner displaced.  If there are no directors in office, then an election of
directors may be held in the manner provided by statute.  If, at the time of
filling any vacancy or any newly created directorship, the directors then in
office shall constitute less than a majority of the whole board (as constituted
immediately prior to any such increase), the Court of Chancery may, upon
application of any stockholder or stockholders holding at least ten percent of
the total number of the shares at the time outstanding having the right to vote
for such directors, summarily order an election to be held to fill any such
vacancies or newly created directorships, or to replace the directors chosen by
the directors then in office.

     Section 3.  The business of the corporation shall be managed by or under
     ----------
the direction of its board of directors which may exercise all such powers of
the corporation and do all such lawful acts and things as are not by statute or
by the certificate of incorporation or by these by-laws directed or required to
be exercised or done by the stockholders.

                       Meetings of the Board of Directors

     Section 4.  The board of directors of the corporation may hold meetings,
     ----------
both regular and special, either within or without the State of Delaware.

     Section 5.  The first meeting of each newly elected board of directors
     ----------
shall be held at such time and place as shall be fixed by the vote of the
stockholders at the annual meeting and no notice of such meeting shall be
necessary to the newly elected directors in order legally to constitute the
meeting, provided a quorum shall be present.  In the event of the failure of the
stockholders to fix the time or place of such first meeting of the newly elected
board of directors, or in the event such meeting is not held at the time and
place so fixed by the stockholders, the meeting may be held at such time and
place as shall be specified in a notice given as hereinafter provided for
special meetings of the board of directors, or as shall be specified in a
written waiver signed by all of the directors.

     Section 6.  Regular meetings of the board of directors may be held without
     ----------
notice at such time and at such place as shall from time to time be determined
by the board.

     Section 7.  Special meetings of the board may be called by the chief
     ----------
executive officer on three
<PAGE>

days' notice to each director, either personally or by mail or by telegram;
special meetings shall be called by the chief executive officer or secretary in
like manner and on like notice on the written request of two directors unless
the board consists of only one director; in which case special meetings shall be
called by the chief executive officer or secretary in like manner and on like
notice on the written request of the sole director.

     Section 8.  At all meetings of the board a majority of the directors shall
     ----------
constitute a quorum for the transaction of business and the act of a majority of
the directors present at any meeting at which there is a quorum shall be the act
of the board of directors, except as may be otherwise specifically provided by
statute or by the certificate of incorporation.  If a quorum shall not be
present at any meeting of the board of directors the directors present thereat
may adjourn the meeting from time to time, without notice other than
announcement at the meeting, until a quorum shall be present.

     Section 9.  Unless otherwise restricted by the certificate of incorporation
     ----------
or these by-laws, any action required or permitted to be taken at any meeting of
the board of directors or of any committee thereof may be taken without a
meetings, if all members of the board or committee, as the case may be, consent
thereto in writing, and the writing or writings are filed with the minutes of
proceeding of the board or committee.

     Section 10. Unless otherwise restricted by the certificate of incorporation
     -----------
or these by-laws, members of the board of directors, or any committee designated
by the board of directors, may participate in a meeting of the board of
directors, or any committee, by means of conference telephone or similar
communications equipment by means of which all persons participating in the
meeting can hear each other, and such participation in a meeting shall
constitute presence in person at the meeting.
<PAGE>

                            Committees Of Directors

     Section 11.  The board of directors may, by resolution passed by a majority
     -----------
of the whole board, designate one or more committees, each committee to consist
of one or more of the directors of the corporation.  The board may designate one
or more directors as alternate members of any committee, who may replace any
absent or disqualified member at any meeting of the committee.  In the absence
or disqualification of a member of a committee, the member or members thereof
present at any meeting and not disqualified from voting, whether or not he or
they constitute a quorum, may unanimously appoint another member of the board of
directors to act at the meeting in the place of any such absent or disqualified
member.

     Any such committee, to the extent provided in the resolution of the board
of directors, shall have and may exercise all the powers and authority of the
board of directors in the management of the business and affairs of the
corporation, and may authorize the seal of the corporation to be affixed to all
papers which may require it; but no such committee shall have the power or
authority in reference to amending the certificate of incorporation, adopting an
agreement of merger or consolidation, recommending to the stockholders the sale,
lease or exchange of all or substantially all of the corporation's property and
assets, recommending to the stockholders a dissolution of the corporation or a
revocation of a dissolution, or amending the by-laws of the corporation; and,
unless the resolution or the certificate of incorporation expressly so provide,
no such committee shall have the power or authority to declare a dividend or to
authorize the issuance of stock.  Such committee or committees shall have such
name or names as may be determined from time to time by resolution adopted by
the board of directors.

     Section 12.  Each committee shall keep regular minutes of its meetings and
     -----------
report the same to the board of directors when required.

                           Compensation of Directors

     Section 13.  Unless otherwise restricted by the certificate of
     -----------
incorporation or these by-laws, the board of directors shall have the authority
to fix the compensation of directors. The directors may be paid their expenses,
if any, of attendance at each meeting of the board of directors and may be paid
a fixed sum for attendance at each meeting of the board of directors or a stated
salary as director.  No such payment shall preclude any director from serving
the corporation in any other capacity and receiving compensation therefor.
Members of special or standing committees may be allowed like compensation for
attending committee meetings.
<PAGE>

                              Removal of Directors

     Section 14. Unless otherwise restricted by the certificate of incorporation
     -----------
or by-law, any director or the entire board of directors may be removed, with or
without cause, by the holders of a majority of shares entitled to vote at an
election of directors.

                                   Article IV

                                    Notices

     Section 1.  Whenever, under the provisions of the statutes or of the
     ----------
certificate of incorporation or of these by-laws, notice is required to be given
to any director or stockholder, it shall not be construed to mean personal
notice, but such notice may be given in writing, by mail, addressed to such
director or stockholder, at his address as it appears on the records of the
corporation, with postage thereon prepaid, and such notice shall be deemed to be
given at the time when the same shall be deposited in the United States mail.
Notice to directors may also be given by telegram or telecopier.

     Section 2.  Whenever any notice is required to be given under the
     ----------
provisions of the statutes or of the certificate of incorporation of these by-
laws, a waiver thereof in writing, signed by the person or persons entitled to
said notice, whether before or after the time stated therein, shall be deemed
equivalent thereto.

                                   Article V

                                    Officers

     Section 1.  The officers of the corporation shall be chosen by the board of
     ----------
directors and shall be a chief executive officer, a president, a secretary and a
treasurer.  The board of directors may also choose vice-presidents, giving them
such designations (including without limitation the designations of executive
vice-president and senior vice-president) as the board may determine, and one or
more assistant vice-presidents, assistant secretaries and assistant treasurers.
Any number of offices may be held by the same person, unless the certificate of
incorporation or these by-laws otherwise provide.

     Section 2.  The board of directors at its first meeting after each annual
     ----------
meeting of stockholders shall choose a chief executive officer, a president, one
or more vice-presidents, a secretary and a treasurer.

     Section 3.  The board of directors may appoint such other officers and
     ----------
agents as it shall deem
<PAGE>

necessary who shall hold their offices for such terms and shall exercise such
powers and perform such duties as shall be determined from time to time by the
board.

     Section 4.  The salaries of all officers and agents of the corporation
     ----------
shall be fixed by the board of directors.

     Section 5.  The officers of the corporation shall hold office until their
     ----------
successors are chosen and qualify.  Any officer elected or appointed by the
board of directors may be removed at any time by the affirmative vote of a
majority of the board of directors.  Any vacancy occurring in any office of the
corporation shall be filled by the board of directors.

                          The Chief Executive Officer

     Section 6.  The chief executive officer shall preside at all meetings of
     ----------
the stockholders and the board of directors, shall have general and active
management of the business of the corporation and shall see that all orders and
resolutions of the board of directors are carried into effect.  He shall execute
bonds, mortgages and other contracts requiring a seal, under the seal of the
corporation, except where required or permitted by law to be otherwise signed
and executed and except where the signing and execution thereof shall be
expressly delegated by the board of directors to some other officer or agent of
the corporation.  In the absence of the chief executive officer or in the event
of his inability or refusal to act, the powers and duties of the chief executive
officer shall be exercised and performed by such executive officer or officers
as may be designated by the board of directors.

                                 Vice Chairman

     Section 7.  The Vice Chairman shall be the Vice Chairman of the Corporation
     ----------
and shall perform such duties and have such powers as the Board of Directors or
the Chief Executive Officer may from time to time prescribe.

                                 The President

     Section 8. The president shall perform such duties and have such powers as
     ----------
the board of directors or the chief executive officer may from time to time
prescribe.

                              The Vice-Presidents

     Section 9.  The vice-presidents shall have such designations (including
     ----------
without limitation the designations of executive vice-president and senior vice-
president) as the board of directors may determine.  The vice-presidents shall
perform such duties and have such powers as the board of directors or the chief
executive officer may from time to time prescribe
<PAGE>

                                 The Secretary

     Section 10.  The secretary shall attend all meetings of the board of
     -----------
directors and all meetings of the stockholders and record all the proceedings of
the meetings of the corporation and of the board of directors in a book to be
kept for that purpose and shall perform like duties for the standing committees
when required.  He shall give, or cause to be given, notice of all meetings of
the stockholders and special meetings of the board of directors, and shall
perform such other duties as may be prescribed by the board of directors or the
chief executive officer, under whose supervision he shall be.  He shall have
custody of the corporate seal of the corporation and he, or an assistant
secretary, shall have authority to affix the same to any instrument requiring it
and when so affixed, it may be attested by his signature or by the signature of
such assistant secretary.  The board of directors may give general authority to
any other officer to affix the seal of the corporation and to attest the
affixing by his signature.

                                 The Treasurer

     Section 11.  The treasurer shall have the custody of the corporate funds
     -----------
and securities and shall keep full and accurate accounts of receipts and
disbursements in books belonging to the corporation and shall deposit all monies
and other valuable effects in the name and to the credit of the corporation in
such depositories as may be designated by the board of directors.

     Section 12.  The treasurer shall disburse the funds of the corporation as
     -----------
may be ordered by the board of directors, taking proper vouchers for such
disbursements, and shall render to the chief executive officer and the board of
directors, at its regular meetings, or when the board of directors so requires,
an account of all his transactions as treasurer and of the financial condition
of the corporation.

     Section 13.  If required by the board of directors, the treasurer shall
     -----------
give the corporation a bond (which shall be renewed every six years) in such sum
and with such surety or sureties as shall be satisfactory to the board of
directors for the faithful performance of the duties of his office and for the
restoration to the corporation, in case of his death, resignation, retirement or
removal from office, of all books, papers, vouchers, money and other property of
whatever kind in his possession or under his control belonging to the
corporation.

                               Assistant Officers

     Section 14.  The assistant vice-presidents, assistant secretaries and
     -----------
assistant treasurers whom the board of directors may appoint from time to time,
as it may deem proper, shall perform such duties and have such powers as the
board of directors or the chief executive officer may from time to time
prescribe.
<PAGE>

                                   Article VI

                             Certificates Of Stock

     Section 1.  Every holder of stock in the corporation shall be entitled to
     ----------
have a certificate, signed by, or in the name of the corporation by, (a) the
chairman or vice-chairman of the board of directors, or the chief executive
officer, or the president or a vice-president, and (b) the treasurer or an
assistant treasurer, or the secretary or an assistant secretary of the
corporation, certifying the number of shares owned by him in the corporation.

          Certificates may be issued for partly paid shares and in such case
upon the face or back of the certificates issued to represent any such partly
paid shares, the total amount of the consideration to be paid therefor and the
amount paid thereon shall be specified.

          If the corporation shall be authorized to issue more than one class of
stock or more than one series of any class, the powers, designations,
preferences and relative, participating, optional or other special rights of
each class of stock or series thereof and the qualification,  limitations or
restrictions of such preferences and/or rights shall be set forth in full or
summarized on the face or back of the certificate which the corporation shall
issue to represent such class or series of stock, provided that, except as
otherwise provided in Section 202 of the General Corporation Law of Delaware, in
lieu of the foregoing requirements, there may be set forth on the face or back
of the certificate which the corporation shall issue to represent such class or
series of stock, a statement that the corporation shall furnish without charge
to each stockholder who so requests the powers, designations, preferences and
relative, participating, optional or other special rights of each class of stock
or series thereof and the qualifications, limitations or restrictions of such
preferences and/or rights.

     Section 2.  Any of or all the signatures on the certificate may be
     ----------
facsimile.  In case any officer, transfer agent or registrar who has signed or
whose facsimile signature has been placed upon a certificate shall have ceased
to be such officer, transfer agent or registrar before such certificate is
issued, it may be issued by the corporation with the same effect as if he were
such officer, transfer agent or registrar at the date of issue.
<PAGE>

                               Lost Certificates

     Section 3.  The board of directors may direct a new certificate or
     ----------
certificates to be issued in place of any certificate or certificates
theretofore issued by the corporation alleged to have been lost, stolen or
destroyed, upon the making of an affidavit of that fact by the person claiming
the certificate of stock to be lost, stolen or destroyed.  When authorizing such
issue of a new certificate or certificates, the board of directors may, in its
discretion and as a condition precedent to the issuance thereof, require the
owner of such lost, stolen or destroyed certificate or certificates, or his
legal representative, to advertise the same in such manner as it shall require
and/or to give the corporation a bond in such sum as it may direct as indemnity
against any claim that may be made against the corporation with respect to the
certificate alleged to have been lost, stolen or destroyed.

                               Transfer of Stock

     Section 4.  Upon surrender to the corporation or the transfer agent of the
     ----------
corporation of a certificate for shares duly endorsed or accompanied by proper
evidence of succession, assignation or authority to transfer, it shall be the
duty of the corporation to issue a new certificate to the person entitled
thereto, cancel the old certificate and record the transaction upon its books.

                               Fixing Record Date

     Section 5.  In order that the corporation may determine the stockholders
     ----------
entitled to notice of or to vote at any meeting of stockholders or any
adjournment thereof, or to express consent to corporate action in writing
without a meeting, or entitled to receive payment of any dividend or other
distribution or allotment of any rights, or entitled to exercise any rights in
respect of any change, conversion or exchange of stock or for the purpose of any
other lawful action, the board of directors may fix, in advance, a record date,
which shall not be more than sixty nor less than ten days before the date of
such meeting, nor more than sixty days prior to any other action.  A
determination of stockholders of record entitled to notice of or to vote at a
meeting of stockholders shall apply to any adjournment of the meeting; provided,
however, that the board of directors may fix a new record date for the adjourned
meeting.

                            Registered Stockholders

     Section 6.  The corporation shall be entitled to recognize the exclusive
     ----------
right of a person registered on its books as the owner of shares to receive
dividends, and to vote as such owner, and to hold liable for calls and
assessments a person registered on its books as the owner of shares, and shall
not be bound to recognize any equitable or other claim to or interest in such
share or shares on the part of any other
<PAGE>

person, whether or not it shall have express or other notice thereof, except as
otherwise provided by the laws of Delaware.

                                  Article VII

                               General Provisions

                                   Dividends

     Section 1.  Dividends upon the capital stock of the corporation, subject to
     ----------
the provisions of the certificate of incorporation, if any, may be declared by
the board of the directors at any regular or special meeting, pursuant to law.
Dividends may be paid in cash, in property, or in shares of capital stock,
subject to the provisions of the certificate of incorporation.

     Section 2.  Before payment of any dividend, there may be set aside out of
     ----------
any funds of the corporation available for dividends such sum or sums as the
directors from time to time, in their absolute discretion, think proper as a
reserve or reserves to meet contingencies, or for equalizing dividends, or for
repairing or maintaining any property of the corporation, or for such other
purpose as the directors shall think conducive to the interest of the
corporation, and the directors may modify or abolish any such reserve in the
manner in which it was created.

                                Annual Statement

     Section 3.  The board of directors shall present at each annual meeting,
     ----------
and at any special meeting of the stockholders when called for by vote of the
stockholders, a full and clear statement of the business and condition of the
corporation.
                                     Checks

     Section 4.  All checks or demands for money and notes of the corporation
     ----------
shall be signed by such officer or officers or such other person or persons as
the board of directors may from time to time designate.

                                  Fiscal Year

     Section 5.  The fiscal year of the corporation shall be fixed by resolution
     ----------
of the board of directors.
                                      Seal

     Section 6.  The corporate seal shall have inscribed thereon the name of the
     ----------
corporation, the year of its organization and the words "Corporate Seal,
Delaware." The seal may be used by causing it or a facsimile thereof to be
impressed or affixed or reproduced or otherwise.
<PAGE>

                                  Article VIII

               Florida General Corporation Act - Section 607.109

     Section 1.  As permitted by Section 607.109(5) of the Florida General
     ----------
Corporation Act, the provisions of Section 607.109(5) of the Florida General
Corporation Act shall not apply to control-share acquisitions of shares of the
corporation.

     Section 2.  As permitted by Section 607.109(11) of the Florida General
     ----------
Corporation Act, the corporation hereby elects not to be governed by the
provisions of Section 607.109(11); accordingly, in the event control shares
acquired in a control-share acquisition are accorded full voting rights and the
acquiring person has acquired control shares with a majority or more of all
voting power, shareholders of the corporation shall not have dissenters' rights
as provided under Section 607.109(11) of the Florida General Corporation Act.

                                   Article IX

                                   Amendments

     Section 1.  These by-laws may be altered, amended or repealed or new by-
     ----------
laws may be adopted by the stockholders or by the board of directors, when such
power is conferred upon the board of directors by the certificate of
incorporation, at any regular meeting of the stockholders or of the board of
directors or at any special meeting of the stockholders or of the board of
directors if notice of such alteration, amendment, repeal or adoption of new by-
laws be contained in the notice of such special meeting.  If the power to adopt,
amend or repeal by-laws is conferred upon the board of directors by the
certificate of incorporation, it shall not divest or limit the power of the
stockholders to adopt, amend or repeal by-laws.

                                   * * * * *