During the transition periods from the neo-democracy period to the socialism period, the Chinese Communist Party had accumulated enriched experiences in leading the socialist transformation of private ownership of production means. Based on summarizing these experiences, Mao Zedong created the Marxism socialist transformation theory with Chinese characteristics, which had made an important contribution to Marxism-Leninism and international communist movements. For the time being, we still need to expound the contents and the significance of that important contribution of Mao Zedong from the theoretical perspective.