An engine valve forging system includes a molding forging die having a circular hole stem molding portion continued to a tip end of a head type molding portion, to mold an engine valve by extrusion-forging a material from the head type molding portion to the stem molding portion by an upper die, and a stem guide forging die which is coaxially disposed to communicate with a tip end of the stem molding portion, and has a guide portion for a stem portion of an engine valve extruded from the stem molding portion, and a plurality of stem curve restraining portions having a shape gradually tapering toward a central shaft line from a rear end portion to a tip end portion are formed continuously along the central shaft line of the guide portion in the guide portion, to be capable of manufacturing high-precision engine valves with less stem curve.