The utility model belongs to the technical field of belong to colliery trolley -bus auxiliary transportation equipment in the pit, concretely relates to a power assembly that is used for explosion -proof electric drive vehicle in colliery has solved the electric drive vehicle and can not satisfy the colliery complicated problem that changes the operating mode demand in the pit. The power assembly is connected with linkage and frame through passing a bridge, and the power assembly uses the axletree to inlay the planet decelerator who is equipped with the explosion proof machine and takes wet braking from inside to outside as the center within wheel hub. The utility model discloses an in -wheel motor speed reduction driven mechanism pattern has driving and parking braking function simultaneously, having left out the required mechanical type of traditional vehicle and having controld gearshift, clutch, derailleur, transmission shaft and mechanical differential mechanism etc. Made actuating system and whole car structure simplify, effective usable space is big, and transmission efficiency improves. This power assembly can make the motor operation under high rotational speed, has higher specific power and efficiency, small, light in weight, and the climbing performance is good, can guarantee to obtain when vehicle low -speed moves great steady torque.