To solve the problem of performance testing for gap of network security special products, a test method for gap performance was studied. Two test methods including the use of iPerf software and IXIA hardware were designed. Both test methods can be applied to the test of gap performance. At the same time, a test method for the performance requirements of gap in the national standards was also analyzed, and a comparative analysis was made with the performance requirements of network security special products. Finally, the throughput and system delay performance for the gap of network security special products are tested through experiments. The distribution results of the 14 gap products are given.