An electric circular saw includes a housing, a switch trigger arranged on the housing, a switch controlling rod for limiting the travel range of the switch trigger, a base plate, a depth support arranged on the base plate and a connecting rod for limiting the travel range of the depth support. The electric circular saw further includes an movable control member having a driving portion for driving the first connecting rod and a limiting portion for limiting the switch controlling rod, and the moving distance from the driving portion to a contact surface between the driving portion and the first connecting rod is larger than or equal to the moving distance from the limiting portion to a contact surface between the limiting portion and the switch controlling rod.