in order to make it easy to change the size of a cam device in the course of press mold design , there is provided a cam device including : a cam holder ; a cam slider ; and a cam driver , wherein the cam devices are grouped depending on the basis of width dimensions in combination of hardness of a sliding contact surface of the cam holder and a sliding contact surface on the cam slider end , and hardness of a cam surface of the cam driver and a cam surface of the cam slider , and the design structures of the respective groups are determined in such a manner that the maximum process ability in a certain group among the groups is larger than the minimum process ability of an adjacent group having a larger width dimension , and smaller than the maximum process ability in an adjacent group having a smaller width dimension .