A power tool and a control circuit thereof by which electric energy can be recovered into a battery pack while an electric motor is braked. The control circuit includes a battery, the electric motor, an operation switch, a first control switch, a second control switch, a controller and an inductive element. The control circuit has a discharging state, a braking state and a charging state. In the charging state, the operation switch is in a second switched-on state, the first control switch is switched on, the second control switch is switched off, the battery, the inductive element, the operation switch, the electric motor and the first control switch form a charging circuit, and the electric motor charges the battery. The controller is electrically connected with the operation switch, the first control switch and the second control switch, respectively.