The work aims to study the reverse design method that deploys 3D solid modeling to 2D structure on irregular carton. Using sheet metal module of Creo, the methods and disciplines for different sorts of irregular carton were analyzed. Three kinds of modeling methods suitable for different carton shape were put forward. Metal flattening results of irregular carton deformed from rectangular block modeling were summarized. In conclusion, the reverse design method based on Creo sheet metal module can reduce the dependence on the designer's skills, and speed up the development process for new box type.