Currently, a series of ecological environmental problems have been brought about by high-intensity intervention of human beings, and ecological security is regarded as one of the most important national survival strategies. A methodology of urban eco-security evaluation has been introduced, including a conceptual framework of pressure-state-response (PSR) model, setting-up of the indicator system of urban eco-security evaluation (ISUESE) and empirical research. By virtue of the mean-deviation method, the weight coefficient of every indicator is confirmed. It has been found that the top three indicators are: per capita area of paved road, per capita area of cultivated land and green coverage rate of built-up area, which has a relatively prominent status in he urban ecological security. A calculation procedure of fuzzy comprehensive evaluation (FCE) method is applied in empirical research. The Mianyang statistical data during the period of 2005-2012 shows that eco-security keeps a favorable trend, but criticality security and slight insecurity are dominant. It has also been found that insecurity membership degree (MD) of environment pressure accounts for a very large proportion of total pressure. Membership degrees of criticality security and security in environment state are increasing gradually, and as far as environment response is concerned, security is significantly increased.