The variable speed hydraulic drive system is a new kind of pressure and flow compound type power source. The complex structure of hydraulic system could not only be simplified by this power system, but also energy saved and noise reduced. The load of hydraulic pump simulated by two mutual-driving servo motors and the speed and torque measurement program based on LabVIEW were introduced. It is convenient to measure the control characteristic of the variable speed hydraulic drive system through the program and the simulated load of hydraulic pump.