[Objective] The evolution of ecological environment at Jiaozuo City, He'nan Province in the past 20 years was studied in order to provide reference for the transformation of other resource exhausted cities.[Methods] The data of five Landsat image data are selected, which included images in 2000,2006,2009,2014 and 2019. The index system including four indicators of green degree, humidity, temperature and dryness, and a evaluation model of remote sensing ecological index (RSEI) was established by principal component analysis, which could evaluate quantitatively the ecological environment quality of Jiaozuo City.[Results] ① From 2000 to 2014, the ecological environment of Jiaozuo City can be presented by shape of an inverted "U", and the quality of ecological environment rose in the next five years. ② The slow urbanization process and the transformation of industrial structure from the secondary industry to the tertiary industry have improved the ecological environment quality of Jiaozuo City. ③ In the regression analysis, the importance of the four selected indicators on the ecological environment in Jiaozuo City was:dryness > humidity > greenness > heat.[Conclusion] Remote sensing ecological index can effectively monitor and evaluate the ecological environment quality of resource exhausted cities.