To stop an actuator without complicating a circuit at the time of non-input.

When products of pressures supplied to a first and second pressure receiving surfaces 11a, 11b of a main spool 11 directly or through an orifice from a pilot depressurization valve 16 in no inputted current condition to a proportional solenoid 14 and areas thereof are equal, the main spool 11 of a main flow regulating valve 10 is in neutral condition, and prescribed gaps are formed among the main spool 11, an integral nozzle 12 and a flapper 13. In this condition, a pressure oil leaking into an annular groove 1e through an annular groove 1d from a pressure port P returns to a tank 4 through a tank port T from a returning line 1h after passing into a sub-flow regulating valve 30, and is prevented from flowing into a controlling port C so that a load of actuator can be kept in state where it stops.