The invention discloses a miniature purely electric car chassis layout structure, which comprises a square truss, wherein the square truss is convex to a passenger cabin, the front part of the square truss is fixedly arranged on a middle transverse beam of a car body, the back part of the square truss is fixedly arranged on a back transverse beam of the car body, a power battery pack assembly is arranged in the square truss, a low-voltage module is arranged in a front cabin skeleton, a high-voltage power module is arranged in a back cabin skeleton, and a cooling water pipe, a brake steel pipe and a parking brake flexible shaft are arranged at the two sides of the power battery pack assembly. The miniature purely electric car chassis layout structure has the advantages that the layout spaces of high-voltage and lower-voltage electric appliances of the electric car are independently arranged, so the electromagnetic interference is reduced; the battery pack is arranged by the new regular framework type truss, so while the safety ground clearance of the battery is guaranteed, the trafficability of the whole car and the comfortability of passengers are guaranteed, the capacity of a battery of the battery pack is increased, and the driving mileage of the whole car is increased; the power driving system assembly adopts the rear drive back layout method, so the climbing capability of the miniature purely electric car is effectively improved, and the front axial load and back axial load of the whole car reach the ideal distribution ratio of 50:50.