A pump displacement control device includes: a servo piston that changes a tilt angle; a flow rate control spool that is displaced corresponding to an input pressure; a power control spool that is displaced corresponding to a discharge pressure of the pump; a control pressure regulating spool that regulates a control pressure which controls the servo piston; and a feedback lever connected to the servo piston and the control pressure regulating spool. The feedback lever directly abut on either one of the flow rate control spool or the power control spool for regulating the control pressure.