The utility model provides a hanging device used for the suspension and heat treatment of a vehicle axle and a hanger adopting the hanging device. The hanging device comprises a clamping chuck structure and a hanging rod structure used for hanging the clamping chuck structure, wherein the clamping chuck structure comprises a clamping chuck, through which the end projection of the vehicle axle passes, and a clamping sleeve structure padded between the end projection of the vehicle axle and the clamping chuck. During the heat treatment process, a hanging projection is machined at the end part of the vehicle axle, then the vehicle axle is hung vertically in a way that the end projection of the vehicle axle passes through the clamping chuck, the vehicle axle is put down after the clamping sleeve structure is padded between the end projection and the clamping chuck, and under the action of self gravity of the vehicle axle, the clamping sleeve structure is pressed between the projection and the clamping chuck, so that the vehicle axle is vertically hung during the heat treatment. The use of the hanging device can avoid the fabrication of the unusable pin-hole structure at the end part of the vehicle axle, thereby not only eliminating the drilling process but also increasing the material utilization rate.