Abstract: Starting from the connotation of Marx's theory of fairness and justice, and based on the study of socialist practice such as social revolution, land reform, socialist transformation and social welfare system in the early days of the People's Republic of China, this paper maintains that Marx's fairness and justice, whose primary requisition is to guarantee the ownership of property is the primary value of the system design for the People's Republic of China. This requisition laid a series of institutional foundations for socialism with Chinese characteristics. The principle of fairness priority makes the socialist thought of fairness and justice deeply root in the hearts of the people, creates a good institutional environment for future reform and market economy, and forms the logical starting point of self-confidence in the socialist system with Chinese characteristics today.