To increase connection ability of a release device and to easily correspond to a changed position of a clutch.

In a release device 40 of an automotive clutch 10, a collet 55 engaged with a collet engaging portion 52 disposed on an inner peripheral portion of a retainer 51 is held by a collet holding means (C ring 53) disposed to the retainer 51, and the collet 55 and a release bearing 42 are engaged with each other at projecting and recessed portions thereof. Further, the release device 40 is constituted by holding a diaphragm spring 17 engaged with a spring engaging portion 57 disposed on a peripheral portion of the retainer 51 by a spring holding means (C ring 58) disposed to the retainer 51.