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                                                                     Exhibit 3.1


                         AMENDED AND RESTATED BY-LAWS

                                      OF

                      MEDIACOM COMMUNICATIONS CORPORATION


                                   ARTICLE I

                                 Stockholders
                                 ------------

     Section 1. Annual Meeting. A meeting of stockholders of the Corporation
                --------------
shall be held annually at such place within or without the State of Delaware, at
such time and on such date as may from time to time be fixed by the Board of
Directors, for the election of directors and for the transaction of such other
business as may come before the meeting.

     Section 2. Special Meetings. Special meetings of stockholders of the
                ----------------
Corporation may be called by the Board of Directors or the Chief Executive
Officer, and shall be called by the Secretary upon the written request of
stockholders of record holding at least a majority in number of the issued and
outstanding shares of the Corporation entitled to vote at such meeting. Special
meetings shall be held at such places within or without the State of Delaware,
at such time and on such date as shall be specified in the call thereof. At any
special meeting, only such business may be transacted which is related to the
purpose or purposes set forth in the notice of such special meeting.

     Section 3. Notice of Meetings. Written notice of each meeting of
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stockholders stating the place, date and hour thereof and, unless it is an
annual meeting, the purpose or purposes for which the meeting is called and that
it is being issued by or at the direction of the person or persons calling the
meeting, shall be given personally or by mail, not less than ten nor more than
sixty days before the date of such meeting, to each stockholder entitled to vote
at such meeting. If mailed, such notice is given when deposited in the United
States mail, with postage thereon prepaid, directed to the stockholder at his or
her address as it appears on the record of stockholders or, if he or she shall
have filed with the Secretary a written request that notices to
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him or her be mailed to some other address then directed to him or her at such
other address.

     Section 4. Waiver of Notice. Notice of any meeting of stockholders need not
                ----------------
be given to any stockholder who submits a signed waiver of notice, in person or
by proxy, whether before or after the meeting. The attendance of any stockholder
at a meeting in person or by proxy, without protesting prior to the conclusion
of the meeting the lack of notice of such meeting, shall constitute a waiver of
notice by him or her.

     Section 5. Adjournment. When any meeting of stockholders is adjourned to
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another time or place, it shall not be necessary to give any notice of the
adjourned meeting if the time and place to which the meeting is adjourned are
announced at the meeting at which the adjournment is taken, and at the adjourned
meeting any business may be transacted that might have been transacted on the
original date of the meeting. However, if after such adjournment the Board of
Directors fixes a new record date for the adjourned meeting, a notice of the
adjourned meeting shall be given to each stockholder of record on the new record
date entitled to vote at such meeting.

     Section 6. Quorum. Except as otherwise provided by law, the holders of a
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majority of the shares entitled to vote at any meeting of stockholders, shall
constitute a quorum thereat for the transaction of any business. When a quorum
is once present to organize a meeting, it is not broken by the subsequent
withdrawal of any stockholders. The stockholders present may adjourn a meeting
despite the absence of a quorum.

     Section 7. Proxies. Every stockholder entitled to vote at a meeting of
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stockholders or to express consent or dissent without a meeting may authorize
another person or persons to act for him or her by proxy. Every proxy must be
signed by the stockholder or his or her attorney-in-fact. No proxy shall be
valid after the expiration of eleven months from the date thereof unless
otherwise provided in the proxy. Every proxy shall be revocable at the pleasure
of the stockholder executing it, except as otherwise provided by law.

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     Section 8. Voting. Every stockholder of record shall be entitled at every
                ------
meeting of stockholders to one vote for every share standing in his or her name
on the record of stockholders. Directors shall, except as otherwise required by
law, be elected by a plurality of the votes cast at a meeting of stockholders by
the holders of shares entitled to vote in such election. Whenever any corporate
action, other than the election of directors, is to be taken by vote of the
stockholders, it shall, except as otherwise required by law, be authorized by a
majority of the votes cast at a meeting of stockholders by the holders of shares
entitled to vote thereon.

     Section 9. Action Without a Meeting. Any action required or permitted to be
                ------------------------
taken by stockholders by vote may be taken without a meeting on written consent,
setting forth the action so taken, signed by the holders of all outstanding
shares entitled to vote thereon.

     Section 10. Record Date. The Board of Directors may fix, in advance, a
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date, which date shall not be more than sixty nor less than ten days before the
date of any meeting of stockholders nor more than sixty days prior to any other
action, as the record date for the purpose of determining the stockholders
entitled to notice of or to vote at any meeting of stockholders or any
adjournment thereof, or to express consent to or dissent from any proposal
without a meeting, or for the purpose of determining stockholders entitled to
receive payment of any dividend or the allotment of any rights, or for the
purpose of any other action. When a determination of stockholders of record
entitled to notice of or to vote at any meeting of stockholders has been made as
provided herein, such determination shall apply to any adjournment thereof,
unless the Board of Directors fixes a new record date for the adjourned meeting.

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                                  ARTICLE II

                                   Directors
                                   ---------

     Section 1. Number and Qualifications. The Board of Directors shall consist
                -------------------------
of one or more members. The number of directors shall be fixed by the Board of
Directors. Directors need not be stockholders of the Corporation. Each of the
directors shall be at least eighteen years of age.

     Section 2. Election and Term of Office. At each annual meeting of
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stockholders, directors shall be elected to hold office until the next annual
meeting of stockholders. Each director shall hold office until the expiration of
such term, and until his or her successor has been elected and qualified, unless
he or she shall sooner die, resign or be removed.

     Section 3. Meetings. A meeting of the Board of Directors shall be held for
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the election of a Chairman of the Board of Directors, for the election of
officers and for the transaction of such other business as may properly come
before such meeting as soon as practicable after the annual meeting of
stockholders. Other regular meetings of the Board of Directors may be held at
such times as the Board of Directors may from time to time determine. Special
meetings of the Board of Directors may be called at any time by the Chief
Executive Officer or by a majority of the directors then in office. Meetings of
the Board of Directors shall be held at the principal office of the Corporation
in the State of Delaware or at such other place within or without the State of
Delaware as may from time to time be fixed by the Board of Directors.

     Section 4. Notice of Meetings; Adjournment. No notice need be given of the
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first meeting of the Board of Directors after the annual meeting of stockholders
or of any other regular meeting of the Board of Directors, provided the time and
place of such meetings are fixed by the Board of Directors. Notice of each
special meeting of the Board of Directors and of each regular meeting the time
and place of which has not been fixed by the Board of Directors, specifying the
place, date and time thereof, shall be given personally, by mail or telegraphed
to each director at his or her address as such address appears upon the books of
the Corporation at least two

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business days (Saturdays, Sundays and legal holidays not being considered
business days for the purpose of these By-Laws) before the date of such meeting.
Notice of any meeting need not be given to any director who submits a signed
waiver of notice, whether before or after the meeting, or who attends the
meeting without protesting, prior thereto or at its commencement, the lack of
notice to him or her. Notice of any directors' meeting or any waiver thereof
need not state the purpose of the meeting. A majority of the directors present,
whether or not a quorum is present, may adjourn any meeting to another time and
place. Notice of any adjournment of a meeting of the Board of Directors to
another time or place shall be given to the directors who were not present at
the time of the adjournment and, unless such time and place are announced at the
meeting, to the other directors.

     Section 5. Quorum; Voting. At any meeting of the Board of Directors, a
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majority of the entire Board of Directors shall constitute a quorum for the
transaction of business or of any specified item of business. Except as
otherwise required by law, the vote of a majority of the directors present at
the time of the vote, if a quorum is present at such time, shall be the act of
the Board of Directors.

     Section 6. Participation by Telephone. Any one or more members of the Board
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of Directors or any committee thereof may participate in a meeting of the Board
of Directors or such committee by means of a conference telephone or similar
communications equipment allowing all persons participating in the meeting to
hear each other at the same time. Participation by such means shall constitute
presence in person at a meeting.

     Section 7. Action Without a Meeting. Any action required or permitted to be
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taken by the Board of Directors or any committee thereof may be taken without a
meeting if all members of the Board of Directors or such committee consent in
writing to the adoption of a resolution authorizing the action. The resolution
and the written consents thereto by the members of the Board of Directors or
such committee shall be filed with the minutes of the proceedings of the Board
of Directors or such committee.

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     Section 8. Committees. The Board of Directors, by resolution adopted by a
                ----------
majority of the entire Board of Directors, may designate from among its members
an Executive Committee and other committees, each consisting of three or more
directors. Each such committee, to the extent provided in such resolution, shall
have all the authority of the Board of Directors, except that no such committee
shall have authority as to the following matters: (a) the submission to
stockholders of any action that needs stockholders' approval pursuant to law,
(b) the filling of vacancies in the Board of Directors or in any committee, (c)
the fixing of the compensation of the directors for serving on the Board of
Directors or on any committee, (d) the amendment or repeal of these By-Laws, or
the adoption of new By-Laws, or (e) the amendment or repeal of any resolution of
the Board of Directors which by its terms shall not be so amendable or
repealable. The Board of Directors may designate one or more directors as
alternate members of any such committee, who may replace any absent member or
members at any meeting of such committee. Each such committee shall serve at the
pleasure of the Board of Directors.

     Section 9. Removal; Resignation. Any or all of the directors may be removed
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for cause by vote of the stockholders, and any of the directors may be removed
for cause by action of the Board of Directors. Any director may resign at any
time, such resignation to be made in writing and to take effect immediately or
on any future date stated in such writing, without acceptance by the
Corporation.

     Section 10. Vacancies. Newly created directorships resulting from an
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increase in the number of directors and vacancies occurring in the Board of
Directors for any reason may be filled by vote of the Board of Directors or by
vote of the stockholders. If any newly created directorship or vacancy is to be
filled by vote of the Board of Directors and the number of directors then in
office is less than a quorum, such newly created directorship or vacancy may be
filled by vote of a majority of the directors then in office. A director elected
to fill a vacancy, unless elected by the stockholders, shall hold office until
the next meeting of stockholders at which the election of directors is in the
regular order of business, and until his or her successor

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has been elected and qualified, and any director elected by the stockholders to
fill a vacancy shall hold office for the unexpired term of his or her
predecessor unless, in either case, he or she shall sooner die, resign or be
removed.

                                  ARTICLE III

                                   Officers
                                   --------

     Section 1. Election; Qualifications. At the first meeting of the Board of
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Directors and as soon as practicable after each annual meeting of stockholders,
the Board of Directors shall elect or appoint a Chief Executive Officer, one or
more Vice-Presidents, a Secretary and a Treasurer, and may elect or appoint at
such time and from time to time such other officers as it may determine.  No
officer need be a director of the Corporation.  Any two or more offices may be
held by the same person, except the offices of Chief Executive Officer and
Secretary.  When all of the issued and outstanding stock of the Corporation is
owned by one person, such person may hold all or any combination of offices.

     Section 2. Term of Office; Vacancies. All officers shall be elected or
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appointed to hold office until the meeting of the Board of Directors following
the next annual meeting of stockholders. Each officer shall hold office for such
term and until his or her successor has been elected or appointed and qualified
unless he or she shall earlier resign, die, or be removed. Any vacancy occurring
in any office, whether because of death, resignation or removal, with cause, or
any other reason, shall be filled by the Board of Directors.

     Section 3. Removal; Resignation. Any officer may be removed by the Board of
                --------------------
Directors with cause. Any officer may resign his or her office at any time, such
resignation to be made in writing and to take effect immediately or on any
future date stated in such writing, without acceptance by the Corporation.

     Section 4. Powers and Duties of the Chief Executive Officer. The Chief
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Executive Officer shall be the chief executive, operating and administrative
officer of the Corporation and

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shall have general charge and supervision of its business, affairs,
administration and operations. The Chief Executive Officer shall from time to
time make such reports concerning the Corporation as the Board of Directors may
direct. The Chief Executive Officer shall preside at all meetings of
stockholders and the Board of Directors. The Chief Executive Officer shall have
such other powers and shall perform such other duties as may from time to time
be assigned to him or her by the Board of Directors.

     Section 5. Powers and Duties of the Vice-Presidents. Each of the Vice-
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Presidents shall have such powers and shall perform such duties as may from time
to time be assigned to him or her by the Board of Directors.

     Section 6. Powers and Duties of the Secretary. The Secretary shall record
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and keep the minutes of all meetings of stockholders and of the Board of
Directors. The Secretary shall attend to the giving and serving of all notices
by the Corporation. The Secretary shall be the custodian of, and shall make or
cause to be made the proper entries in, the minute book of the Corporation and
such books and records as the Board of Directors may direct. The Secretary shall
be the custodian of the seal of the Corporation and shall affix or cause to be
affixed such seal to such contracts, instruments and other documents as the
Board of Directors may direct. The Secretary shall have such other powers and
shall perform such other duties as may from time to time be assigned to him or
her by the Board of Directors.

     Section 7. Powers and Duties of the Treasurer. The Treasurer shall be the
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custodian of all funds and securities of the Corporation. Whenever required by
the Board of Directors, the Treasurer shall render a statement of the
Corporation's cash and other accounts, and shall cause to be entered regularly
in the proper books and records of the Corporation to be kept for such purpose
full and accurate accounts of the Corporation's receipts and disbursements. The
Treasurer shall at all reasonable times exhibit the Corporation's books and
accounts to any director of the Corporation upon application at the principal
office of the corporation during business hours. The Treasurer shall have such
other powers and shall perform such other duties

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as may from time to time be assigned to him or her by the Board of Directors.

     Section 8. Delegation. In the event of the absence of any officer of the
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Corporation or for any other reason that the Board of Directors may deem
sufficient, the Board of Directors may at any time and from time to time
delegate all or any part of the powers or duties of any officer to any other
officer or officers or to any director or directors.

                                  ARTICLE IV

                                    Shares
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     The shares of the Corporation shall be represented by certificates signed
by the Chief Executive Officer or any Vice-President and by the Secretary, an
Assistant Secretary, the Treasurer or an Assistant Treasurer, and may be sealed
with the seal of the Corporation or a facsimile thereof. Each certificate
representing shares shall state upon the face thereof (a) that the Corporation
is formed under the laws of the State of Delaware, (b) the name of the person or
persons to whom it is issued, (c) the number and class of shares which such
certificate represents and (d) the designation of the series, if any, which such
certificate represents.

                                   ARTICLE V

                            Execution of Documents
                            ----------------------

     All contracts, instruments, agreements, bills payable, notes, checks,
drafts, warrants or other obligations of the Corporation shall be made in the
name of the Corporation and shall be signed by such officer or officers as the
Board of Directors may from time to time designate.

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                                  ARTICLE VI

                                     Seal
                                     ----

     The seal of the Corporation shall contain the name of the Corporation, the
words "Corporate Seal", the year of its organization and the word "Delaware".

                                  ARTICLE VII

                                Indemnification
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     The Corporation shall indemnify any person to the full extent permitted,
and in the manner provided, by the General Corporation Law of the State of
Delaware, as the same now exists or may hereafter be amended.

                                 ARTICLE VIII

                                  Fiscal Year
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     The fiscal year of the Corporation shall end on December 31 of each year or
on such other date as shall be determined by the Board of Directors.

                                  ARTICLE IX

                             Amendment of By-Laws
                             --------------------

     Except as otherwise provided by law, these By-Laws may be amended or
repealed, and any new By-Law may be adopted, by vote of the holders of the
shares at the time entitled to vote in the election of any directors or by a
majority of the entire Board of Directors, but any by-law adopted by the Board
of Directors may be amended or repealed by the stockholders entitled to vote
thereon as herein provided.

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