Combined with the actual situation of the west region city of Zunyi, the three subsystems including social, economic and natural environment evaluation index systems of ECC have been built based on the theory of ecological carrying capacity (ECC). In addition, the factor analysis method has been used and the influence factors on the ECC in the economic transition have been gained. The results show that factors of ECC in the three subsystems have different influence: 1) the natural subsystem, which contains factors on the ECC, has obvious limitation, and it has the greatest influence on industrial waste discharge per capita; 2) the social subsystem has a restriction on the ECC, which affects the traffic environment mostly; 3) the economic subsystem has a certain restriction on ECC, which has a large effect on the consumption level per capita.