The purpose of this study is to measure the correlation among sustainable development indexes, and pursue a better way to reduce the dimensions of such original indexes. In the studies of sustainable development index, there is a serious contradiction between increasing the coverage of indexes and decreasing the information overlapping of indexes, for generally more indexes means more overlapping among them. Most of the leading studies in China and abroad in resent years select relatively large amount of indexes. For example, the indexes of UNSCD have 134 indexes in the beginning and 58 indexes after modified in 2000, the indexes by the government of UK included 118 indexes, the indexes by a research group of Chinese Academy of Sciences is 231 indexes. This study select 46 indexes which are often used among them, and process the correlation analysis on them. The result shows that most of them correlate each other in some ways, i.e. the overlapping information is significant.Then the dimension reduction model is developed based on statistic technique, and eight components that are regarded as independent comprehensive indexes are derived. Assume component is: z₁，z₂，…，z_n，the original indexed are:x₁，x₂ ，…，x_m，then the dimention reduction model are：
z₁=α₁₁x₁+α₁₂x₂+…+α_1mx_m
z₂=α₂₁x₁+α₂₂x₂+…+α_2mx_m
…
z_n=α_n1x₁+α_n2x₂+…+α_nmx_m
indicates the coefficient of the models. The values of are listed in Table. 4.
    According to the scoring of comprehensive indexes, the sustainable development conditions of 31 Chinese provincial regions (not including Hong Kong, Macao, and Taiwan) are sorted. The ranking of these regions is: ①Shanghai, ②Beijing, ③Tianjin, ④Jiangsu, ⑤Guangdong, ⑥Fujian, ⑦Zhejiang, ⑧Shandong, ⑨Heilongjiang, ⑩Hubei, B₁₁Hebei, B₁₂Liaoning,B₁₃Henan, B₁₄Hainan,B₁₅Jilin,B₁₆Hunan,B₁₇Anhui,B₁₈Jiangxi,B₁₉Guangxi, B₂₀-Xinjiang, B₂₁-Chongqing,B₂₂Yunnan, B₂₃Sichuan,B₂₄Tibet, B₂₅Inner Mongolia, B₂₆Shannxi,B₂₇Ningxia, B₂₈Gansu, B₂₉-Shanxi, B₃₀-Guizhou,B₃₁-Qinghai.