FUEL CELL SYSTEM

A fuel cell system includes: a fuel cell (34) generating electricity using a fuel and an oxidant gas; a reforming unit (33) generating the fuel from a raw reforming material from a raw reforming material supply source and reforming water, and supplying the fuel to the fuel cell; a desulfurizer (11a6) removing a sulfur component contained in the raw reforming material and supplying the desulfurized raw reforming material to the reforming unit; a raw reforming material supply pipe (11a) causing the raw reforming material to be fed to the desulfurizer; a raw material pump (11a5) provided in the raw reforming material supply pipe and supplying the raw reforming material to the desulfurizer; a recycling fuel pipe (39) causing a portion of the fuel to return to an introduction side of the raw material pump; and a pressure control valve (11a4) provided on the raw reforming material supply pipe.