Abstract: Based on the composition and properties of gasoline gum, the standard determination method for measuring existent gum，solvent washed gum and unwashed gum were systematically analyzed to find the reasons for the different analysis results of gum content. The changes of quoted standard for gasoline gum test method and the interactions between additives and solvent washed gum were introduced. It is found that the abuse of gasoline additives is the primary reason that causes the superstandard of unwashed gum and abnormal work of engine. The rational and efficient use of additives with lower polarity, less non-hydrocarbon element and lower unwashed gum is the foundation of effective running of engine.