<p>A high-pressure fuel supply pump having a fuel relief path for connecting a high-pressure fuel path downstream of a discharge valve (8) for discharging fuel pressurized in a pressurizing chamber (11) to a low-pressure fuel path upstream of an inlet valve (30) or the pressurizing chamber, a check valve being provided in the fuel relief path as a relief valve for allowing the fuel to flow only to the low-pressure fuel path or the pressurizing chamber (11), wherein an energy attenuating mechanism is provided in a discharge path on a side facing the discharge valve (8) upstream of the relief valve in the fuel relief path so as to prevent an instantaneous pressure rise caused in the discharge path from propagating to the relief valve.</p>
