To simply form a safety cover lock mechanism and to release a top dead center lock with good operability.

In a bench circular saw 1 with an upper table, a safety cover lock mechanism 30 including a lock lever 31 that engages with an outer cover 15B in a cover position for covering a saw blade 8 at a top dead center of a body 7 and restricts lowering of the body 7 is provided with one operation lever 32 which is connected with the lock lever 31, includes an operation plate 44 disposed adjacent to, parallel to and rearwardly of a handle 14, and causes the lock lever 31 to move from an engagement position to a disengagement position through an operation of gripping the operation plate 44 by a hand.