As the most important process in the pretreatment process of body-in-white in the paint shop,the stability of the traditional phosphating process is crucial to the performance of body-in-white anticorrosion and other properties.In the face of the current market demand for lightweight aluminum alloy body-inwhite,the proportion of galvanized sheet has decreased and the content of aluminum sheet has increased in the current new models.This paper mainly introduces the purpose of the increase in aluminum content of the body-in-white,the specific impact of the traditional phosphating process and the corresponding solution strategy to increase the stability of the phosphating process to improve the quality of the body is of great significance.