Reduction gearbox, drive axle and vehicle

The invention discloses a reduction gearbox, a drive axle and a vehicle. The reduction gearbox comprises a mounting base, a shell, a planetary reduction structure and a connecting shaft. And the shell is arranged on the mounting seat and is connected with the driving wheel. The planetary speed reduction structure comprises a first planetary speed reduction mechanism and a second planetary speed reduction mechanism, and the installation base is constructed to be a planet carrier of the second planetary speed reduction mechanism. The connecting shaft is rotatably arranged on the mounting base, the first planetary speed reducing mechanism is in transmission fit with the shell and the connecting shaft, and the second planetary speed reducing mechanism is in transmission fit with the shell and the connecting shaft. According to the reduction gearbox, the larger reduction ratio can be obtained through the first planetary reduction mechanism and the second planetary reduction mechanism, compared with a reduction gearbox in the related technology, the reduction gearbox in the implementation mode can provide the reduction ratio meeting the working requirement of a large-tonnage vehicle, the applicability of the reduction gearbox is improved, and the cost is reduced. And stable and reliable operation of the vehicle is ensured.