Based on the background, this project is to study China current building market status and promote a series of policies to enhance existing building green retrofit. From the point of view of current situation and development of existing buildings in China, the project will carry out research on development, technical measures and industry form, analyze the relationship of existing building retrofit and green employment along with the key issues of industry chain, make analysis of specific implementation of investment and financing mechanism in the existing building green retrofit field and put forward mechanism and suggestion to promote existing building green retrofit.