Abstract: Provided is a high pressure fuel pump including: a body formed in a side surface thereof with a discharge hole; a pressurizing device for generating a suction force for sucking fuel supplied from a fuel tank and a pressurizing force for pressurizing the fuel at a high pressure; a seal carrier coupled to a lower portion of the body and coupled with the pressurizing device; a flow control valve coupled to one side of the body, for controlling a supply flow rate and a discharge pressure of the fuel; and a pressure relief valve for relieving an abnormal high pressure by transferring a part of discharged fuel to a low pressure space formed in the lower portion of the body when the abnormal high pressure exceeding a preset pressure limit is generated in a fuel supply system for supplying the fuel discharged through the discharge hole to an injector.