Servo-valve that controls fluid discharged from a nozzle discharge port by displacing the nozzle, and that drives an actuator. The servo-valve includes a receiver provided with a first inflow port into which the fluid discharged from the discharge port flows. At least either the discharge port or the inflow port is a non-circular opening formed such that the amount of change in the area of overlap of the discharge and inflow ports occurring when the nozzle is displaced from the initial position is larger than in cases where the discharge port and the inflow port are of circular form of the same area. The increased amount whereby the area of overlap between the discharge and inflow ports changes when the nozzle is displaced from the initial position lets the fluid flow into the inflow port more quickly, improving the response speed of the actuator.