The present invention is directed to an electromechanical brake device for securing the structural reliability and improving the stability even when overloading. The electromechanical brake device configured to brake by pressing a disk-shaped disc, which is rotated with motor vehicle wheels, with a pair of friction pads, and including a piston unit configured to move the friction pads in a direction of the disc, including: an internal shaft connected to an external motor so as to rotate when the motor is driven; an external shaft, in which an end of the internal shaft is inserted, configured to rotate together when the internal shaft is rotated, and to which the piston unit is connected so as to move in the disc direction; and a load control unit provided between the internal shaft and the external shaft, so that the external shaft is rotated together when the internal shaft is rotated, and the internal shaft and the external shaft are rotated at different speeds when a load of a predetermined value or more is applied between the internal shaft and the external shaft.