A high-pressure pump has an elastic member arranged in a damper chamber between a first diaphragm and a second diaphragm. The elastic member is always in contact with both diaphragms while the high-pressure pump is operated. When the diaphragms are further vibrated due to a resonance under a situation where a frequency of the pressure pulsation of low-pressure fuel is in agreement with the characteristic frequency of the diaphragms, the elastic member restricts the deformation of the diaphragms. Therefore, the resonance of the first diaphragm and the second diaphragm can be restricted.