The world great changes are the important variables and key factors that influence the development trend of the relationship between capitalism and socialism，which are reconstructing the coexistent relationship of capitalism and socialism and their coexistent space.At present,the relationship between western developed countries and newly－developing countries is undergoing a deep adjustment. The interaction and competition game are obvious，and the communication and mutual learning of different cultures and the clashes of all kinds of trends of political thoughts are extremely active. The political model and developing experiences of western capitalism become dim and dark while socialism with Chinese characteristics in China in the 21st century invigorates itself and becomes the mainstay of revitalizing world socialism. The replacement of capitalism by socialism is a long historical process，which requires the maturation of all the subjective and objective conditions，and at last the superiority of socialist system to the capitalist is dependent on the successful examples of socialism.

Editor: Zhong Yao

Studies on Marxism.2019.No.10.