A variable displacement pump includes a pump structural member configured to change volumes of a plurality of working chambers by rotation of a rotor, so as to introduce oil through an inlet port into the working chambers and to discharge the oil through a discharge port, and further configured to oscillate a cam ring by a discharge pressure introduced into a control oil chamber. A first coil spring is provided to force the cam ring in a direction for increasing of a rate of change of the working-chamber volume. A second coil spring is provided to force the cam ring in a direction for decreasing of the rate of change of the working-chamber volume. The first and second coil springs are laid out on both sides of an arm portion of the cam ring in a manner so as to be opposed to each other.