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                                                                     EXHIBIT 11


                         MARINE MANAGEMENT SYSTEMS, INC.
                    COMPUTATION OF EARNINGS PER COMMON SHARE

                                   (UNAUDITED)



<TABLE>
<CAPTION>
                                                              Nine Months Ended                      Three Months Ended
                                                          Sept. 30           Sept. 30           Sept. 30           Sept. 30
                                                            1997               1996               1997               1996
                                                         -----------        -----------        -----------        -----------
<S>                                                      <C>                <C>                <C>                <C>         
Common shares outstanding at January 1:                    2,701,110          2,007,576          4,421,120          2,701,110

IPO offering, May 7, 1997                                  1,440,000

Other stock transactions in 1996, net:                                         693,534
Other stock transactions in 1997, net:                       280,010
                                                         -----------        -----------        -----------        -----------


Common shares outstanding on September 30,:                4,421,120          2,701,110          4,421,120          2,701,110

Adjustment to weighted average:                             (764,449)          (255,671)

Stock options                                                 46,218             71,290             46,218             71,290

Warrants:                                                    347,219            347,219            347,219            347,219

Convertible securities                                                          377,777                               377,777

Treasury stock adjustments                                  (339,023)          (540,222)          (416,777)          (540,222)

Less:  receivable shares                                                        (77,767)                              (77,767)
                                                         -----------        -----------        -----------        -----------

Weighted average outstanding shares @ September 30         3,711,085          2,623,736          4,397,780          2,879,407
                                                         ===========        ===========        ===========        ===========

Net loss for periods ending September 30,                $(2,110,912)       $  (789,461)       $  (661,568)       $  (367,706)
Adjustment for assumed 10% interest on proceeds
  from sales and proceeds used on treasury                                       18,015                                48,552

Adjusted net loss:                                       $(2,110,912)       $  (771,446)       $  (661,568)       $  (319,154)
                                                         ===========        ===========        ===========        ===========

Earnings (loss) per share:                                     (0.57)             (0.29)             (0.15)             (0.11)
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                 See accompanying Notes to Financial Statements