The stand or fall of control system hardware platform directly affects the safe and stable operation of HVDC transmission system. Field testing is the most rapid and effective means of verifying that hardware platform. According to the features and performance of each board, the scheme of test system of HVDC control hardware platform of MACH2 system is put forward. The test system is based on the board replacement principle. The functionality and performance of the board are tested by means of a combination of software and hardware. The practical testing application shows that the test system can correctly perform the function and performance testing of the board of MACH2 hardware platform. The test system is easy to opearte and the result is reliable. At the same time, reliability and stability of the hardware platform operation will be improved.