A switch mechanism for a pneumatic tool includes a rotating body and a lever. The rotating body has a surface, wherein a combining portion is disposed on the surface. The lever is slidably disposed in the combining portion, wherein the lever includes a first operating end and a second operating end, and either one of the first operating end and the second operating end protruding from the pneumatic tool or both the first operating end and the second operating end protruding from the pneumatic tool are controlled by pushing the lever along an extending direction of the combining portion.