Abstract: A chain saw with a safety brake includes a cutter bar which is pivotally connected to the saw frame. A brake band arranged around the clutch hub of the gear sprocket has one band end connected to the frame and the other band end connected to the pivotal cutter bar. A spring between the saw frame and the cutter bar urges the cutter bar about the pivot to a safety position in which the brake band grips the clutch drum and prevents chain movement. Manual pressure of the cutter bar against the work material overcomes the bias of the spring to pivot the cutter bar to the working position and release the brake band and enable the cutting chain to travel. Release of pressure on the cutter bar as for instance when the bar severs the work material causes the cutter bar to return to the safety position under spring bias, with the brake band engaged with the clutch drum and chain movement stopped. Manual overrides are disclosed to enable chain movement when the cutter bar is not pressed against the work.