An electric brake device configured to brake a wheel or to maintain a stopped state of the wheel, including: a friction member; a piston configured to advance for pushing the friction member onto a rotary body; a motion converting mechanism having an input shaft and configured to convert rotation of the input shaft into an advancing and retracting movement of the piston; an electric motor; and a rotation transmitting mechanism configured to transmit rotation of the electric motor as the rotation of the input shaft, the rotation transmitting mechanism including a drive pulley connected to the electric motor, a driven pulley connected to the input shaft, a belt wound around the two pulleys, and a speed change mechanism configured to change a ratio of a rotation speed of the driven pulley to a rotation speed of the drive pulley in dependence on tension of the belt between the two pulleys.