HIGH-PRESSURE FUEL PUMP

An object of the present invention is to reduce erosion due to cavitation in proximity to a valve seat in a high-pressure fuel supply pump including a fuel flow passage having a bent portion in proximity to the valve seat, formed therein. The high-pressure fuel supply pump includes fuel passages 10S and 10P interconnecting with a pressurizing chamber of fuel in which volume varies due to reciprocating motion of a plunger to be in the reciprocation motion, and fluid valves 203 and 214S formed on the fuel passage. The fuel valves are included in a valve seat 214S and a valve member 203. The fuel passages include a gap passage portion 10S formed in a gap between the valve seat and the valve member, and a bent passage portion 10P extending in a bent direction on the downstream side of the gap passage portion. In a case where a backflow direction of the fuel is defined as a reference, in terms of a passage surface on the side of an inner circumference of a bent passage portion including the gap passage portion and the bent passage portion, a recess portion 214A is formed on an end portion on the upstream side of a passage surface 214D included in the side of the bent passage portion.