To provide a position control system for suppressing oil leakage from the valves and performing accurate position control of the controlled object by controlling oil flow rate using poppet type solenoid valves, in the position control system that performs position control of an object to be operation-controlled by a hydraulic actuator.

The position control system 100, that performs position control of an object 105 to be operation controlled by a hydraulic actuator 101, includes solenoid valves 1-4 to drive and control the hydraulic actuator 101, a pump 8 to supply oil to the hydraulic actuator 101 through the solenoid valves 1-4, valve actuating means 12 and 13 for opening/closing the solenoid valves 1-4 with pulse width modulation control, a position detecting means 6 for detecting the position of the controlled object 105, an oil temperature detecting means 10 for detecting the temperature of oil supplied to the solenoid valves 1-4, and a control calculation means 20 for deciding a duty ratio of the pulse width, based on the position detected by the position detecting means 6 and the oil temperature detected by the oil temperature detecting means 10, controlled by the valve actuating means 12 and 13.