An optimal design method of corrugated box dimension was put forward to reduce the cost of packaging material and storage, in which the object of study is assumed by taking product as quasi-square and outer packaging container as corrugated box. The optimal design scheme was introduced, which was to establish material saving corrugated box model and optimized pallet load model and to carry out optimization in the processes of corrugated box design, pallet load, and storage space in turn to improve area utilization and cube utilization of pallet and reduce packaging cost. The optimization flowchart of corrugated box dimension was presented.