Abstract: In this research, an assessment indicators system for urban ecologization level of Chongqing was established. This system consists of 41 core indicators which were selected from 44 indicators by principal component analysis. The 44 indicators were chosen from 64 basic indicators from the five supporting sub-systems of urban ecosystem based on correlation analysis and coefficient of variation analysis. Furthermore, the degree of Chongqing urban ecologization development from 2005 to 2012 was calculated by using the entropy weight method and relevant formula, and the degree of Chongqing urban ecologization harmony from 2005 to 2012 was calculated using gray correlation analysis method. Finally the urban ecologization index was obtained and classified into five levels. Results show that the urban ecologization level of Chongqing was improved step-by-step, with some fluctuations in certain years, which was overall consistent with the actual situation. In 2005 the value of urban ecologization index was 0.36(level Ⅲ),but rose to 0.73(level Ⅱ) in 2012.However, long-term endeavor is required to go up to level I, and its further development is facing double challenges both from integrality and structure.

Key words: urban ecologization level, evaluation index system, urban ecological development, urban ecological harmony, urban ecological index , Chongqing