<PAGE>
 
                                                                   EXHIBIT 10.22
                         STOCKHOLDER VOTING AGREEMENT


     Stockholder Voting Agreement (the "Agreement") dated as of July 31, 1998,
by and among John W. Kluge ("Kluge"), Chase Manhattan Bank, and John W. Kluge
Trustees U/A Dated May 30, 1984 As Amended By and For John W. Kluge (the
"Trust"), and PHP Healthcare Corporation, a Delaware corporation (the
"Company").

     WHEREAS, the Trust beneficially owns 1,625,000 shares of common stock, $.01
par value per share, of the Company ("Common Stock");

     WHEREAS, the Trust desires to acquire up to an additional 575,000 shares of
Common Stock; and

     WHEREAS, as a condition to permitting the Trust to acquire additional
shares of Common Stock, the Company requires that Kluge and the Trust
(collectively, the "Kluge Parties") enter into this Agreement.

     NOW, THEREFORE, the parties hereto agree as follows:

                                   ARTICLE I

                                     TERM

     1.1.  Term.  The term of this Agreement (the "Term") shall commence on the
           ----                                                                
date hereof and continue until the Kluge Parties beneficially own less than five
percent (5%) of the outstanding Common Stock of the Company.

                                  ARTICLE II

                                REPRESENTATIONS
                                ---------------

     2.1.  Representations of the Company.  The Company hereby represents and
           ------------------------------                                    
warrants to the Kluge Parties that (i) the Company has the full legal right,
power and authority to enter into and perform this Agreement, (ii) the execution
and delivery of this Agreement by the Company, and the consummation by it of the
transactions contemplated herein, have been duly authorized by the Company,
(iii) this Agreement constitutes the legal, valid and binding obligation of the
Company, enforceable against the Company in accordance with its terms, except to
the extent that any applicable bankruptcy, insolvency, reorganization,
moratorium or other similar laws or general equitable principles may affect the
enforceability thereof, and (iv) subject to the execution and delivery of this
Agreement by the Kluge Parties, the Board of Directors of the Company has
approved the acquisition by the Kluge Parties of an additional 575,000 shares of
Common Stock for purposes of Section 203 of the Delaware General Corporation Law
and the Rights Agreement, dated as of April 10, 1992, by and between the Company
and Riggs National Bank, N.A., as rights agent.
<PAGE>
 
     2.2.  Representations of the Kluge Parties.  The Kluge Parties hereby
           ------------------------------------                           
represent and warrant to the Company that (i) the Kluge Parties have the full
legal right, power and authority to enter into and perform this Agreement, (ii)
the execution and delivery of this Agreement by the Kluge Parties, and the
consummation by them of transactions contemplated herein, have been duly
authorized by the Kluge Parties, (iii) this Agreement constitutes the legal,
valid and binding obligation of the Kluge Parties enforceable against the Kluge
Parties in accordance with its terms, except to the extent that any applicable
bankruptcy, insolvency, reorganization, moratorium or other similar laws or
general equitable principles may affect the enforceability thereof, (iv) on the
date hereof, the Kluge Parties beneficially own only 1,625,000 shares of Common
Stock, and neither Kluge, the Trust nor any of their affiliates or associates
beneficially owns any other securities of any of the Company, or rights or
interests in any such securities, (v) none of the Kluge Parties has any
agreements, arrangements or understandings with any person regarding any
possible stockholder proposal or proxy solicitation with respect to the Company,
or with regard to the acquisition or voting of any securities of the Company,
and (vi) the Kluge Parties have made all filings required to be made under the
Securities Exchange Act of 1934, as amended, and the rules and regulations
thereunder and the information contained in such filings does not contain any
material misstatement or omit to make any statement that in light of the
circumstances in which they were made true and correct in all material respects.


                                  ARTICLE III

                       VOTING; RESTRICTIONS ON TRANSFERS
                       ---------------------------------

     3.1.  Voting of Common Stock.  The Kluge Parties agree that at each meeting
           ----------------------                                               
of stockholders of the Company and in any action by written consent of the
stockholders of the Company, the Kluge Parties shall vote or execute consents in
respect of, or cause to be voted or cause consents to be executed in respect of,
all of the shares of Common Stock, or any other voting securities of the Company
beneficially owned by the Kluge Parties or their affiliates or associates as
follows:

          (a) all shares of Common Stock beneficially owned by the Kluge Parties
or their affiliates or associates and acquired on or after the date of this
Agreement shall be voted, at their option, either (i) in accordance with the
recommendation of the Board of Directors of the Company or (ii) pro rata in the
same manner and proportion that votes (or consents, as the case may be) of the
stockholders of the Company (other than the Kluge Parties) have been cast; and

          (b) after the earlier of (A) Mr. Kluge's death or incapacity or (B)
the date Mr. Kluge ceases to be a trustee and beneficiary of the Trust, the
Kluge Parties shall vote or cause all shares of Common Stock beneficially owned
by the Kluge Parties or their affiliates or associates (whether acquired before,
on or after the date hereof) to be voted, at their option, either (i) in
accordance with the recommendation of the Board of Directors of the Company, or
(ii) pro rata in the same manner and proportion that votes (or consents, as the
case may be) of the stockholders of the Company (other than the Kluge Parties)
have been cast.

                                      -2-
<PAGE>
 
The Kluge Parties will ensure that they and their affiliates or associates are
present, in person or by proxy, at all meetings of stockholders of the Company
so that all voting securities beneficially owned by the Kluge Parties or their
affiliates or associates shall be counted for purposes of determining the
presence of a quorum at such meeting.

     3.2.  Irrevocable Proxy.  In the event a Kluge Party shall fail to comply
           -----------------                                                  
with the provisions of Section 3.1 hereof as determined by the Company in its
sole discretion, such Kluge Party agrees that such failure shall result, without
any further action by such Kluge Party, in the irrevocable appointment of the
Chief Executive Officer of the Company, until termination of this Agreement, as
such Kluge Party's attorney-in-fact and proxy pursuant to the provisions of
Section 212(e) of the General Corporation Law of the State of Delaware, with
full power of substitution, to vote, and otherwise act (by written consent or
otherwise) with respect to the shares of Common Stock which such Kluge Party is
entitled to vote at any meeting of stockholders of the Company (whether annual
or special and whether or not an adjourned or postponed meeting) or consent in
lieu of any such meeting or otherwise, in the manner specified in Section 3.1
hereof.  THIS PROXY AND POWER OF ATTORNEY IS IRREVOCABLE AND COUPLED WITH AN
INTEREST.  Each Kluge Party hereby revokes all other proxies and powers of
attorney with respect to the shares of Common Stock which such Kluge Party may
have heretofore appointed or granted, and no subsequent proxy or power of
attorney shall be given or written consent executed (and if given or executed,
shall not be effective) by such Kluge Party with respect thereto.  All authority
herein conferred or agreed to be conferred shall survive the death or incapacity
of each Kluge Party and any obligation of a Kluge Party under this Agreement
shall be binding upon the heirs, personal representatives and successors of such
Kluge Party.

     3.3.  Restrictions on Transfer.  The Kluge Parties shall not, directly or
           ------------------------                                           
indirectly, sell, lend, transfer or otherwise dispose of any of their shares of
Common Stock of the Company (or agree to do so) to any person which, to their
knowledge and after taking into account such sale, would result in the
transferee beneficially owning more than five percent (5%) of the Company's
outstanding Common Stock; provided, however, that the Kluge Parties may sell,
lend, transfer or otherwise dispose of shares of Common Stock in any brokerage
transaction in which the identity of the buyer is unknown or to any Permitted
Transferee (as defined below) that agrees to be bound by the terms of this
Agreement pursuant to a written instrument in form and substance acceptable to
the Company.  For purposes of this Agreement, the term "Permitted Transferee"
means (i) John W. Kluge or Stuart Subotnick, any member of their immediate
families and any issue of Kluge or Mr. Subotnick or any such member; (ii) a
trust solely for the benefit of the individuals referred to in clause (i); (iii)
the guardian or conservator of any of the individuals referred to in clause (i);
(iv) the estate of any of the individuals referred to in clause (i); and (v) and
a corporation, partnership, limited liability company or other entity all of the
outstanding securities of which are owned by any of the persons referred to in
clauses (i), (ii), (iii) or (iv).

                                      -3-
<PAGE>
 
                                  ARTICLE IV

                                 MISCELLANEOUS
                                 -------------

     4.1.  Governing Law.  This Agreement shall be governed and construed in
           -------------                                                    
accordance with the laws of the State of New York without regard to its rules of
conflict of laws.

     4.2.  Successors and Assigns.  Except as otherwise provided herein, the
           ----------------------                                           
provisions hereof shall inure to the benefit of, and be binding upon, the
successors, assigns, heirs, executors and administrators of the Parties.

     4.3.  Entire Agreement; Amendment.  This Agreement constitutes the full and
           ---------------------------                                          
entire understanding and agreement between the Parties with regard to the
subjects related to herein, and neither the Kluge Parties nor the Company shall
be liable or bound to any other party in any manner by any warranties,
representations or covenants except as specifically set forth herein.  Except as
expressly provided herein, neither this Agreement nor any term hereof may be
amended, waived, discharged or terminated other than by a written instrument
signed by the party against whom enforcement of any such amendment, waiver,
discharge or termination is sought.

     4.4.  Notices.  Any notice or other communication in connection with this
           -------                                                            
Agreement shall be made in writing and served by personal delivery (including,
without limitation, courier, Federal Express or other overnight messenger
service), or mailed by United States certified mail, postage prepaid, return
receipt requested, addressed as follows:

           If to the Company, to:

               PHP Healthcare Corporation.
               11440 Commerce Park Drive, Suite 300
               Reston, Virginia  20191
               Attention:  Jack M. Mazur
                           President and Chief Executive Officer
        
        
           With copies to:
        
               PHP Healthcare Corporation.
               11440 Commerce Park Drive, Suite 300
               Reston, Virginia  20191
               Attention:  Ben Rosenbaum
                           General Counsel
        
           and

                                      -4-
<PAGE>
 
               Fried, Frank, Harris, Shriver & Jacobson
               1001 Pennsylvania Avenue, N.W.
               Suite 800
               Washington, DC  20004-2505
               Attention:  Richard A. Steinwurtzel, Esq.
        
        
           If to the Kluge Parties, to:
        
               John W. Kluge
               215 East 67th Street
               New York, NY
        
           and
        
               c/o John W. Kluge
               215 East 67th Street
               New York, NY
        
          With copies to:
        
               Metromedia Company
               One Meadowlands Plaza
               E. Rutherford, NJ  07073
               Attention:  General Counsel
        
          and
        
               Paul, Weiss, Rifkind, Wharton & Garrison
               1285 Avenue of the Americas
               New York, New York  10019-6064
               Attention:  James M. Dubin, Esq.

Any party may send any notice, request, demand, claim, or other communication
hereunder to the intended recipient at the address set forth above using any
other means (including personal delivery, expedited courier, messenger service,
telecopy, telex, ordinary mail, or electronic mail), but no such notice,
request, demand, claim, or other communication shall be deemed to have been duly
given unless and until it actually is received by the intended recipient.  Any
party may change the address to which notices, requests, demands, claims, and
other communications hereunder are to be delivered by giving the other Parties
notice in the manner herein set forth.

     4.5.  Counterparts.  This Agreement may be executed in any number of
           ------------                                                  
counterparts, each of which shall be enforceable against the Parties actually
executing such counterparts, and all of which together shall constitute one
instrument.

                                      -5-
<PAGE>
 
     4.6.  Severability.  The invalidity or unenforceability of any provision of
           ------------                                                         
this Agreement shall not affect the validity or enforceability of any other
provision hereof.

     4.7.  Expenses.  The Kluge Parties and the Company shall each bear their
           --------                                                          
own expenses with respect to this Agreement and the transactions contemplated
hereby.

     4.8.  Construction.  The headings of the Articles, Sections and paragraphs
           ------------                                                        
of this Agreement are inserted for convenience only and shall not be deemed to
constitute part of this Agreement or to effect the construction hereof.  As used
in this Agreement (i) "hereof", "hereunder", "herein" and words of like impact
                       ------    ---------    ------                          
shall be deemed to refer to this Agreement in its entirety and not just a
particular section of this agreement, (ii) "beneficially own" shall have the
                                            ----------------                
meaning of such term within Rule 13d-3 (as such rule is currently in effect)
under the Exchange Act, (iii) "affiliate" and "associate" shall each have the
                               ---------       ---------                     
meaning of such terms within Rule 12b-2 (as such rule is currently in effect)
under the Exchange Act.

     4.9.  Further Assurances.  The Parties agree to use their reasonable
           ------------------                                            
efforts to effectuate this Agreement and the transactions contemplated hereby.

                                      -6-
<PAGE>
 
     IN WITNESS WHEREOF, each of the Parties hereto caused this Agreement to be
executed on its behalf as of the date first above written.


                             PHP HEALTHCARE CORPORATION


                             By:     /s/ Jack M. Mazur
                                     -----------------------------
                             Name:   Jack M. Mazur
                             Title:  President and Chief Executive Officer



                             CHASE MANHATTAN BANK & JOHN W. 
                             KLUGE TRUSTEES U/A DTD 5/30/84 AS 
                             AMENDED BY AND FOR JOHN W. KLUGE


                             By:     /s/ John W. Kluge
                                     -----------------------------
                             Name:   John W. Kluge
                             Title:  



                             /s/ John W. Kluge
                             -----------------------------------------
                             JOHN W. KLUGE

                                      -7-