To investigate the control performance of subsea control module (SCM) hydraulic system at the depth of 2 000 m，the dynamic models of the open and close of valve actuator,long hose and electro-hydraulic valve were established.The simulation of the whole hydraulic system was carried out by AMESim software,and the dynamic performance relations of the system pressure,oil pressure difference and actuator rod displacement were obtained.While,it was to open one and multiple valve actuators on the SCM test device,the influence of the actuator pressure drop on the performance of the hydraulic system was achieved.The results show that the hydraulic system can be used to control the 12 way oil;the time shuting down 8 actuators extends 17 s than that of single actuator in an emergency;the more the oil circuit is opened,the smaller the pressure drops.