Abstract: The legitimacy in political science or political philosophy is different from the legitimacy in law. The former has a deep cultural value appeal, and its essence is that power obtains the "consent" of the people. The legitimacy of the Communist Party of China governance is neither from the sky, nor is it done once for all, but it is the struggle of the Chinese Communist Party, and it is the choice of history and the people. The "Four Creations" and "Nine Musts" of the Communist Party of China emphasized by General Secretary Xi Jinping in his important speech on July 1st in 2021 clearly show the Communist Party's struggle to gain the legitimacy of its governance, historical achievements and future goals. Marxism provides an important cultural value core for the legitimacy of the Communist Party of China. The mass line in Marxist historical materialism, capital ethics criticism in political economy, and scientific socialism’s demand for free value in an ideal society in the future are the value base, the reality of value, and the soul of the legitimacy of the Communist Party of China in power. These three constitute the scientific whole of Marxism.

Key words: Marxism, the Communist Party of China, legitimacy of governance, value identification