To provide a diaphragm pump that is suitable to pump liquid by exerting a sufficient force to pump liquid, suppressing a pulsating flow and preventing a vibration even when used as a liquid pump.

The diaphragm pump comprises a diaphragm body integrally forming a plurality of diaphragm parts, and one discharge valve in a flat plate form arranged substantially at the center of the plurality of diaphragm parts. A drive mechanism for reciprocating drive parts integrated with the diaphragm parts reciprocates the drive parts of the diaphragm parts at a constant phase difference.