PURPOSE: To stably control the action of a hydraulic cylinder.

CONSTITUTION: A pressure compensation circuit 16 outputs control signals to control a serve valve 13 so that a load pressure may become equal to the objective pressure value. A speed compensation circuit 17 outputs control signals to control the servo valve 13 so that a cylinder speed may become equal to the objective speed value. A determination circuit 21 determines to control either loading pressure or cylinder speed based on a pressure comparing signal from a pressure comparing circuit 22 and a speed comparing signal from a speed comparing circuit 23 in the case where either the load pressure or cylinder speed reaches its objective value so as to output determination signal. A change- over switch 18 switches and selects a control signal based on the one mentioned above according to the determination signal from the determination circuit 21 and outputs the signal to the servo valve 13. The action of the hydraulic cylinder is stably controlled by thus always monitoring the load pressure and the cylinder speed and automatically switching pressure control and speed control according to the loading state.