Abstract: Based on the systematic engineerings, a new theory and method are proposed for product design. The whole design method is divided into three phase, i.e., general planning, implementation and quality assessment. In the first phase the seven basic factors should be comprehensively planned for product design: conception, environment, process, objective, contents, methodology and, the quality assessment. During implementation the product design should be done according to the 1+3+X integrated design method, where the 1 implies that a product should be designed with its function optimized and the 3 mean that the method of design should integrate organically the dynamic, intelligent and visual optimizations together. The X reflects a special design method that is required to meet the special conditions necessary to a product. In the final phase the quality of the product designed should be assessed by way of theoretical analysis and testing or user's commissioning.