Abstract: After the failure of Revolution, the Communist Party of China transferred from city to countryside. The composition of its members had changed, with fewer workers and a large increase in the number of peasant members, and the Party was in danger of becoming a "peasant party".On the basis of Marxist class theory and combining the practical experience of agrarian revolution, the Communist Party of China had formed the class theory of Chinese characteristics. Under the guidance of this theory, the Communist Party of China rebuilt its class based on rural farmhands, and maded an important attempt to "proletarianize" the Party's guiding organs.Class theory was an important part of the Party's theoretical construction and had far-reaching historical influence.