The invention provides an electromagnetic clutch inner hub manufacturing method and belongs to the technical field of engineering components. Through the electromagnetic clutch inner hub manufacturingmethod, the problem that an existing clutch inner hub is not suitable for actual batch production is solved. The electromagnetic clutch inner hub manufacturing method comprises the steps of selectinga blank, machining a spline on the sidewall of a shaft hole, conducting cold extrusion pretreatment and conducting cold extrusion forming in sequence, wherein during cold extrusion forming, the blankis placed into a female die of a cold extrusion die, one end of a shaft is inlaid in a locating cavity, and a spline rod penetrates through the shaft hole; the female die and a male die are closed, acenter rod is made to abut against the end face of the spline rod in the die closing process, a molding head applies pressure to the other end of the shaft, and a stop dog with a center hole is formed at the other end of the shaft. According to the electromagnetic clutch inner hub manufacturing method, the selected blank, the spline machining method, the cold extrusion forming method and cold extrusion forming dies are all suitable for actual mass production. Thus, the electromagnetic clutch inner hub manufacturing method is suitable for actual industrial mass production.