The invention discloses a diaphragm positioning anti-falling structure. The diaphragm positioning anti-falling structure comprises a pump body, a diaphragm and a valve plate; the valve plate is located on the upper portion of the diaphragm, a groove is formed in the pump body, a boss capable of being in interference fit with the groove is formed in the position, corresponding to the groove in the pump body, of the diaphragm, and the diaphragm and the pump body are connected in a manner that the groove and the boss are matched. According to the diaphragm positioning anti-falling structure, the boss is made on the diaphragm, the groove is formed in the pump body, through the fit manner, the positioning and anti-falling effect is achieved, the diaphragm can be prevented from moving and falling, and the service life of the pump can be prolonged.