To provide a brake structure wherein energy loss to be caused by axial movements and inclination of first and second rotors is reduced, and a first rotation shaft and a second rotation shaft are standardized.

In a drive unit 11, a first motor 12 and a second motor 13 are placed so that the axis of the first rotation shaft 14 agrees with that of the second rotation shaft 15. In a brake chamber 21 sectioned between the first motor 12 and the second motor 13, the first and second rotors 36, 41, a stator 43, a pair of brake discs 42a, 42b, and a piston 51 are held. The first rotation shaft 14 and a first cylindrical member 31 are fastened together with a first nut 34 with the first rotation shaft 14 inserted. The second rotation shaft 15 and a second cylindrical member 38 are fastened together with a second nut 39 with the second rotation shaft 15 inserted. In the first cylindrical member 31, a recess 33 is formed on the side of the second-motor to hold at least the first nut 34.