The sprinkler is a common special vehicle,which is widely used in landscaping,engineering con-struction,fire fighting and other aspects.Pure electric sprinkler due to the need to output a certain rated power and must load a relatively large battery pack,resulting in the vehicle's rated load(water load)is limited.Based on the analysis of pure electric chassis,the paper optimizes the shape and material of the tank by CAD,so as to reduce the repair mass and improve the rated load(water load),and also provides a technical reference for the lightweight design of the tank of the same kind of special vehicle.