The work aims to study and solve the problem of mismatch between pallet size and application scenario. The pallet structure of metal material was creatively designed. According to the different requirements of the use scene, the length or width of the pallet could be changed on the basis of the original pallet size, and the pallets with different specifications could be derived. The design with variable pallet sizes could solve the problems of the pallet application well, improve the applicability of the pallet in different scenarios, enhance the matching of the pallets with the stored shelves, the handled products and delivery vehicles and improve the standardization of the pallets. It was beneficial to establish a pallet recycling system, improve the utilization of pallets and the efficiency of logistics operations, and reduce logistics costs. The metal pallet based on the variable-size design has better bearing and safety, and it has good market prospects.