In view of the shortcomings of traditional electromagnetic valve,such as electromagnetic lag,an electric servo valve is used to replace the electromagnetic valve to meet the requirements of high thrust and high precision of the attitude and orbit control engine.In order to carry out the hardware in the loop simulation test,a comprehensive performance loading test system was designed based on rotating motor and ball screw.The hardware architecture of the system was built based on PXI bus,and LabVIEW was used to develop the PC software platform.The main program,realtime program and communication mode were designed concretely.In order to suppress the position disturbance of the servo valve and improve the loading accuracy,a feedforward position compensation and force close loop PID control method was proposed.The experimental results show that this system can be used to effectively test the load bearing capacity and displacement output precision of electric servo valve,and the testing results can meet the ‘double ten index’.