To provide a cam device which operates an output shaft by converting constant continuous rotation of an input shaft into composite rotation made by combination of rocking rotation and inconstant speed rotation.

An input shaft 5 is supported by a housing 3 and constantly rotated at a regular speed. The first output shaft 7 is supported by the housing, and the inconstant speed rotation converted from the constant speed continuous rotation through the medium of a rotational motion changing can mechanism 21 is transmitted thereto. A slider member 9 is coaxially provided to the first output shaft 7 in a state of having a relative rotation with the first output shaft restricted by the medium of a relative rotation restricting cam mechanism 31 and being free to relatively displace in the axial direction, and the reciprocating linear motion in the above axial direction converted from the constant speed continuous rotation is thereto transmitted through the medium of a cam link mechanism 41. The second output shaft 11 is restricted to axially travel coaxially with the first output shaft. A motion changing cam mechanism 51 is engaged and interposed between the second output shaft and slider member, and the oscillating rotation of the second output shaft converted from the reciprocating linear motion of a slider member is transmitted thereto. At the same time, the cam mechanism 51 transmits the inconstant speed rotating motion of the slider member to the second output shaft.