Abstract: Changes of ecological footprint can reflect the impact of economic development to ecological environment in mining cities. The study set a mining city——Wu'an city as an example, analyzed quantitatively the relevant indicators of ecological footprint, and used the principal component analysis to study the driving force of ecological footprint. The results show that Wu'an city's ecological footprint is far greater than the ecological capacity; the efficiency of resources use and the diversity of ecological footprint are fairly low; the non-sustainable development becomes increasingly serious. The main driving forces of ecological footprint changes are the economic development level and the level of consumption. In order to promote the sustainable development, Wu'an should both change the mode of economic growth and improve the efficiency of resources use. In addition, it is also necessary to change the way of consumption, to encourage people consuming reasonable, to increase input of the ecological environment construction, and to improve the ecological capacity.