<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS FINANCIAL INFORMATION EXTRACTED FROM THE UNAUDITED 
FINANCIAL STATEMENTS OF NETWORK-1 SECURITY SOLUTIONS, INC. FOR THE PERIOD 
ENDED JUNE 30, 1998 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH 
FINANCIAL STATEMENTS.
</LEGEND>
       
                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1998
<PERIOD-START>                             JAN-01-1998
<PERIOD-END>                               JUN-30-1998
<CASH>                                         634,000
<SECURITIES>                                         0
<RECEIVABLES>                                  697,000
<ALLOWANCES>                                    88,000
<INVENTORY>                                     15,000
<CURRENT-ASSETS>                             1,278,000
<PP&E>                                         769,000
<DEPRECIATION>                                 446,000
<TOTAL-ASSETS>                               3,129,000
<CURRENT-LIABILITIES>                        3,707,000
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                      5,000
<COMMON>                                        17,000
<OTHER-SE>                                   (600,000)
<TOTAL-LIABILITY-AND-EQUITY>                 3,129,000
<SALES>                                        412,000
<TOTAL-REVENUES>                               902,000
<CGS>                                          395,000
<TOTAL-COSTS>                                  667,000
<OTHER-EXPENSES>                             1,769,000
<LOSS-PROVISION>                                18,000
<INTEREST-EXPENSE>                             438,000
<INCOME-PRETAX>                            (1,990,000)
<INCOME-TAX>                                         0
<INCOME-CONTINUING>                        (1,990,000)
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                               (1,990,000)
<EPS-PRIMARY>                                   (1.17)
<EPS-DILUTED>                                   (1.17)