The development experience of some countries shows that the period when the national income rises from the middle-income level to the high-income level is the key period of social transformation. During this period, with the widening income distribution gap among social members and the exchange and integration of various thoughts and cultures, people's interest demands are increasingly diverse, and the independence, selectivity and difference of people's ideological activities are also significantly enhanced, making it more difficult to form social consensus. How to adapt to this profound change, enhance social cohesion and successfully cross the "middle income trap" is an important challenge facing by many countries. At present, China is moving from a middle-income country to a high-income country. Facing the different interests and diverse thoughts and cultures of the people in the transition period, China has maintained long-term social stability and harmony while maintaining sustained economic development, providing rich materials and valuable experience for the study of social cohesion construction, and embarking on a road with Chinese characteristics. This study intends to systematically summarize the practice of building social cohesion in China during the transition period, and on this basis, put forward suggestions from the aspects of increasing social fairness and justice, cultivating common values, strengthening social governance, etc., so as to contribute Chinese wisdom and Chinese solutions to the construction of social cohesion in the world, especially in developing countries.