In a housing, a damper member is placed in a fluid chamber communicated with a pressurizing chamber, at which a plunger is reciprocated to pressurize fuel, and an opening of the fluid chamber is covered with a cover member. The damper member includes first and second-side diaphragms. A first-side support member is located between the damper member and the cover member and is engaged with a first-side outer peripheral portion of the first-side diaphragm and the cover member. A second-side support member is located between the damper member and the housing and is engaged with a second-side outer peripheral portion of the second-side diaphragm and the housing. The first and second-side support members are urged between the housing and the cover member.