A hammer drill includes a switch, an operation member, a lock member, a mode switching member and a linked member. The operation member is normally held in an OFF position and moves to an ON position in response to an external pressing operation. The lock member moves in response to an external operation between a locking position, where the lock member is capable of locking the operation member in the ON position, and a non-locking position, where the lock member is incapable of locking the operation member. The linked member moves to an allowing position for allowing a movement of the lock member when the mode switching member is switched to a switching position corresponding to a hammer mode, and moves to an inhibiting position for inhibiting the movement of the lock member when the mode switching member is switched to a switching position corresponding to a drill mode.