Brake system for automobile is disclosed. The brake system comprises a braking gear for supplying a braking force to an output shaft, a first braking member for making the braking gear stop, an operator for operating the first braking member and a third braking member for selectively making speed change gears stop, and a controller for controlling the operator. The breaking gear meshes continuosly with a driving gear and is coaxially aligned with the output shaft. The first braking member engages the braking gear to connect or disconnect the supply of power from a driving shaft to the braking gear. The controller receives a braking signal generated by a braking treadle and controls the operator to disconnect the supply of power from the driving shaft to the speed change gears and engage the braking gear by an operation of the first braking member.