A high pressure pump for preventing distortion of a sealing surface or a cylinder form. The high pressure pump has an intermediate member including a cylinder body having a pressurizing chamber communicated with a cylinder accommodating a plunger. Fluid in the pressurizing chamber is pressurized by reciprocating the plunger. The intermediate member is arranged between a cover and a flange and is clamped by clamping bolts. An electromagnetic spill valve for receiving reaction force from the pressurizing chamber when the fluid in the pressurizing chamber is pressurized is attached to the cover at a position for reducing the clamping force applied to the intermediate member by the clamping bolts.