To impart both a reciprocation function and a rotational reciprocation function to an output shaft, and to easily changeover the functions.

This power tool has a housing 1; a rotational drive device 2 housed in the housing 1; an output shaft 4 provided within the housing 1 to rotate around the axis and to axially reciprocate, allowing attachment of a tool to its front end; and a cam mechanism 5 for converting rotation movement of the rotational drive device 2 into the reciprocation movement of the output shaft 4. The power tool is provided with a rotation transmission mechanism 6 for transmitting the rotation movement of the rotational drive device 2 to the output shaft 4, so that the rotational drive device 2 can rotationally drive the output shaft 4 with reciprocating the output shaft 4. Connection and disconnection between the rotational drive device 2 and the output shaft 4 through the rotation transmission mechanism 6 can be changed over.