A working-fluid supply system includes: a first pump and a second pump driven by an engine; a first switching valve capable of switching a supply target of the second pump to either one of the discharge side and the suction side of the first pump; a first switching control unit configured to perform a switching control of the first switching valve; and a first pressure control unit configured to perform a control such that pressure on the suction side of the first pump becomes a predetermined first pressure when the first switching valve is switched such that the supply target of the second pump becomes the suction side of the first pump.