An explosion-proof braking device is described, which is configured to be connected to the front flange of an explosion-proof electric motor, the braking device comprising: a shaft (6) connected to the shaft of the motor from the outside, and provided with bearings (7, 8) internal to the device, an electromagnetic brake (11, 12, 13, 14) acting upon said shaft (6), comprising at least one excitation coil (11) and one air gap (10). The shaft (6) is made of a non-magnetic metal alloy, the bearings (7, 8) are so positioned as to lie outside the main flux lines of the magnetic field produced between the coil and the air gap, and the braking device is provided with flame-proof lamination joints of the through or closed type.