Transmission system of alternating-current storage-battery electric forklift truck

The invention relates to a transmission system of an alternating-current storage-battery electric forklift truck. The transmission system comprises a differential mechanism assembly, a speed reducer, a driving axle housing, a left brake, a right brake, a brake drum, a wheel hub, a left half axle and a right half axle. The speed reducer comprises a dual gear, a small dual gear and a pinion. The driving axle housing comprises a left axle housing, a speed-reducer main shell and a right axle housing. The left axle housing comprises a speed-reduction box and a left tubular axle which is connected with the speed-reduction box in sequence, wherein the speed-reduction box is in a clamshell shape, and a left sleeve is located on one side of the upper portion of the speed-reduction box. The speed-reducer main shell comprises a horizontal type barrel-shaped shell, wherein the upper portion of the barrel-shaped shell is a differential mechanism cavity, the lower portion of the barrel-shaped shell is a wheel axle cavity protruded downwards, and the differential mechanism assembly is located in the differential mechanism cavity. The right axle housing comprises a right axle housing body and a right tubular axle, wherein one end of the right axle housing body is in an end cap shape, and a right sleeve is located at the other end of the right axle housing body. The transmission system is compact in structure, good in manufacturability, low in manufacturing cost, good in assembly technology, and convenient to maintain.