To facilitate mounting in and removing from a rotary shaft, by dividing a cam into two parts without deteriorating a function as the cam, in a ring-shaped end cam or peripheral face cam fitted to the rotary shaft.

A rotary cam 10 is vertically split to be divided into two divided bodies 11, so as to facilitate mounting in and removing from a rotary shaft A. Here, a connection line 17 of both the divided bodies 11 in a part of a cam surface 12 is tilted relating to a line extended in a radial direction. Since a roller-shaped cam follower B passes through the connection line 17 in a condition simultaneously brought into contact with the cam surface 12 of both the divided bodies 11, the cam follower B is accurately and smoothly operated.