A power tool in the form of an electric disc grinder has a driving motor for driving a grinding wheel that performs a grinding or polishing operation on a workpiece, a motor housing that houses the driving motor, a rear cover that is mounted to a rear end region of the motor housing and forms together with the motor housing a grip to be held by a user, and a power switch including an operating lever that extends longitudinally on both of the motor housing and the rear cover and is operated by gripping with a user's hand, and a switch part that is disposed within the rear cover and actuated by operation of the operating lever to control energization of the driving motor and connected to the operating lever through an opening.