An injection molding die for molding a needle-equipped syringe includes a male die including a core pin, and a through hole, a female die including a female die opening part, a concave part, and an injection needle holding hole; a support rod that is insertable from a pin proximal end into the through hole, wherein the support rod is configured to contact and support a needle proximal end of an injection needle inserted from a pin distal end, and to push the needle proximal end to a vicinity of the pin distal end; and a resin injection gate configured to allow resin to be injected to a cavity formed by the concave part and the core pin inserted from the female die opening part.