An automatic test system of high speed digital circuit based on VME bus is designed in this paper to test high speed signal processing modules of the certain artillery position reconnaissance and fire adjusting radar. The system can simulate working environment of the radar. VME test module can provide optical signal, RapidIO signal and so on needed by test. The test result is up loading to the system management platform through network of VME controller. The system is applied in testing high speed signal processing modules of the certain radar successfully. This test system can realize the interface test of VME bus; the test of three RapidIO which transport frequency is 3.125Gbps; the test of four optical signal which transport frequency is 2Gbps. The research and test results show the system can resolve the test problem of high speed digital circuit based on VME bus.