To provide an electromagnetic multiple disc clutch that can improve controllability at torque capacity control by reducing the hysteresis of torque transmission between disengagement and engagement, in an electromagnetic multiple disc clutch used as a starting clutch or the like.

The electromagnetic multiple disc clutch comprises a main clutch 30 for engaging disengaging an input side and an output side torque transmission member, a pilot clutch 40 disengaged by an operating means, and a cam mechanism 50 for engaging the main clutch via a pressing system by means of cam thrust force. An input drum comprises a first input drum 31 and a second input drum 32, and has a socket-and-spigot part 32a having a socket/spigot on an outside diameter face of either the first input drum 31 or the second input drum 32, and the socket-and-spigot part 32a has a plurality of ball splines 37 spaced out evenly along an input drum circumference.