Abstract:  Subsea control module （SCM) is the core unit of subsea production system. The realization of the control function of the SCM mainly relies on the hydraulic power to provide the driving force for the subsea valves. The running， installation and recovery of SCM is an important issue in the subsea production systems. Ordinary screw mainly works with sliding friction， for which the efficiency is usually 0.3~0.6. Compared with the ball screw， the drive efficiency and the drive speed are far less. Because of its self locking， ordinary screw is still widely used in the lifting mechanism. In this paper， according to the actual project case， through the mechanical analysis and calculation， for the power source of the screw drive mechanism， i. e., hydraulic motor, the power and the minimum output torque are obtained. The results can be used as the reference data of the type selection of hydraulic motor.