In recent years, in order to meet the relevant national requirements and to accumulate the points of new energy vehicles production, joint ventures within the GAC Group have submitted to the Guangzhou Plant of Guangzhou Automobile Group Motor Co., Ltd.(hereafter referred to as "GAC Motor") the demand for processing painted new energy vehicles. At the same time, the KD production model was adopted after the Xinjiang Plant of GAC Motor was put into production, and the required painted vehicles are provided by the Guangzhou Plant of GAC Motor. Based on the vehicle body automatic painting process of Guangzhou Plant of GAC, this paper proposes a method that uses the uniqueness of the vehicle identification number(VIN) to accurately identify the painted vehicles required by ventures, which solves the problem of automatic production of multiple models on the same line, realizing precise production, and greatly improves production efficiency.