Abstract: At The beginning of the new-democratic revolution, the advanced intellectuals and the revolutionaries began to establish CCP and the Socialist Youth League across Sichuan Province. The whole process was full of hardships. Because political atmosphere and social environment was not the same everywhere in Sichuan, the difficulties and challenges encountered by underground party are also not identical. Because of geographic isolation, out-of-date information circulation, and so on, the early construction activities of the Party in Sichuan Province started relatively late. There were a lot of problems during the process, such as the success in work relying on the specific person too much, common dispute caused by personal feelings, the loose discipline in the Party, and the unstable Party organizations, which were the natural defects during the early stage of the Party construction. These disadvantages were finally overcome by CCP in Sichuan. The experience and lessons during these processes could deepen our understandings about the path, difficulties and countermeasures during the development of early local organizations of CCP.