Abstract: A method for mounting the rotor and the brake of an electrical brake motor whose brake comprises a plate (4) which can be axially moved between the rotor (2) and a backplate (5) due to the opposing actions of the magnetic field and of a spring (8). The method consists in simultaneously mounting the rotor (2), the brake plate (4) and the backplate (5) onto the shaft of the motor, by pushing them by means of a tool (14) pushing directly, on the one hand, the plate and the rotor and, on the other hand, the backplate, in such a manner that the air-gap value (n) is exclusively and automatically determined by the configuration of the tool and of the plate.