Exploring the connection and exchanges between the Chinese Communist Party (CCP) and the Japanese Communist Party (JCP) has become an important research. In addition to helping to understand the long-standing practice of international communism programs and struggles, it can provide a broader perspective of the CCP diplomacy to comprehend the Chinese government's diplomatic decision-making and attitude toward Japan. Through the historical research approach, this article clearly sorts out the four periods of the communication between these two parties: Firstly, the period of mutual assistance before 1949. Secondly, the close period of the communication after the CCP's political construction in 1949 and before the outbreak of the Cultural Revolution in 1966. Thirdly, from 1966 to 1997, the relationship between the two parties turned sour, and then went into the dawn of improving relations. Finally, the two parties have turned to normal exchanges since 1997 to the present.