An apparatus for controlling operation of a walk-behind electric lawn mower equipped with an electric motor, a blade cutter connected to the electric motor and a rechargeable battery mounted connected to the electric motor and a motor driver circuit. In the apparatus, when an instruction to stop the electric motor is inputted, the operation of the motor driver circuit is controlled to output regenerative electric current from three-phase coils of the electric motor. At that time, it is determined whether a rotational speed of the electric motor is equal to or less than a switching rotational speed and when it is, the motor driver circuit is controlled to switch from the regenerative braking to short-circuit braking that short-circuits the three-phase coils of the electric motor.