The invention provides a parallel air-cooling heat dissipation structure for a stepped battery module. The parallel air-cooling heat dissipation structure comprises a heat dissipation box body and a stepped frame; the stepped frame is arranged in the heat dissipation box body and is used for dividing the heat dissipation box body into an air incoming region, an air outgoing region and a battery pack mounting region; the battery pack mounting region is provided with a plurality of battery packs mounted in the stepped frame; a left frame comprises an upper top plate, a lower bottom plate, partition plates and side plates; the upper top plate and the lower bottom plate are both stepped; steps between the upper top plate and the lower bottom plate are divided into a plurality of battery slotsthrough the plurality of partition plates; the side plates are arranged between adjacent partition plates; and the left frame and a right frame are both installed in the heat dissipation box body in asliding mode. With the parallel air-cooling heat dissipation structure for the stepped battery module of the invention adopted, batteries can work in an optimal temperature range; the temperature consistency of the batteries during working is ensured; the size of the box body is greatly reduced; and the mass energy density and volume energy density of a system are improved.