The work aims to improve weather resistance of automobile coatings by selecting appropriate test conditions and methods. Universally accepted environmental benchmark test stand conditions were compared, natural exposure test conditions of domestic environment experimental station were analyzed, regularity and correlation between artificial accelerated aging test and natural outdoor exposure test were further analyzed, weather resistance of same coating with different substrates, and suggestions on quality control of high automobile decorative varnish and coating were proposed. In terms of light lost rate, 3000 h artificial accelerated aging test had poor correlation with 12 & 15 months natural exposure in Qionghai (damp and hot) and Dunhuang (dry and hot) (both＜0.8), and negative correlation with 12 and 15 months natural exposure in Jiangjin (acid) and Mohe (cold) with great fluctuation data. 3000~5000 hours artificial aging test is recommended to inspect automobile decorative coating varnish. At least two damp and hot as well as dry and hot zones are selected for natural exposure test to be conducted for at least 2 years. Due to particularity of automobile products, the artificial accelerated aging test shall focus on: (1) selection of test conditions; (2) strengthening permeation of water molecules to coating, humidity control and guarantee the moisture content in the coating in the coating during the test; (3) simulating day and night temperature difference change.