The utility model discloses an arrangement structure of a small pure electric vehicle chassis. The arrangement structure comprises a square truss protruding in the passenger compartment direction, the front portion of the square truss is fixed to a vehicle body middle cross beam, the rear portion of the square truss is fixed to a vehicle body rear cross beam, a power battery packet assembly is arranged in the square truss, front-row seat mounting points are arranged above the square truss, rear-row seat mounting points are arranged above the rear portion of the square truss, and a low-pressure module is arranged in a front compartment framework. A high-pressure power module is arranged in a rear compartment framework. A cooling water pipe, a brake steel pipe and a parking brake flexible shaft are arranged on the two sides of the power battery packet assembly. The arrangement spaces of a high-voltage electric appliance and a low-voltage electric appliance of an electric vehicle are independent, electromagnetic interference is reduced, the safety ground clearance of a battery packet is guaranteed, meanwhile, the whole vehicle trafficability characteristic and the comfort for passengers are guaranteed, the battery capacity of the battery packet is increased, and the driving range of the whole vehicle is increased. The slope climbing capacity of the small pure electric vehicle is effectively improved, and meanwhile the ideal distribution of 50:50 of shaft loads of the front portion and the rear portion of the whole vehicle is achieved.