Abstract: In the period of Anti-Japanese War,the following are the main reasons for the CCP's constitutionalism construction: the need of the overall war of resistance,the influence of Com-intern and the request of the CCP's regime construction.The CCP's constitutionalism construction mainly contains the construction of thought and theory and the construction of political system.The CCP's constitutionalism construction has important characteristic,and it also gives us many important enlightenments.