Water resources and socio-economic system is a large complicated system.If portraying this system completely,it needs quite a number of indices and along with losing values in research.Therefore,the paper utilized the principal component analysis method to reduce seven indices which complete describe the water resources and socio-economic development to three indices.According to the development condition of each city in Sichuan,it scientifically gave out the co-ordinate degree and rank of water resources a...