Abstract: The study on evaluation of ecological carrying capacity is of great significance to the regional sustainable development. In this paper, 130 cities of the Yangtze River Economic Zone are taken for example. We conducted a quantitative study on ecological carrying capacity based on both ecological support and ecological pressure, by building a relatively comprehensive evaluation system of ecological carrying capacity with the evaluation index weighted via entropy method. The ecological support, ecological pressure and ecological carrying capacity of the cities located in Yangtze River Economic Zone were evaluated. Furthermore, the spatial pattern of ecological support, ecological pressure and ecological carrying capacity of the Yangtze River Economic Zone in 2003, 2008 and 2013 were discussed and the impact factors were analyzed. The results showed: (1) in both 2003 and 2008, the spatial pattern of ecological support in the Yangtze River Economic Zone exhibited the best performance of the upstream area, which was better than the downstream area and even better than the midstream area; between 2003 and 2008, ecological support of midstream area and upstream area increased, while that  of downstream area decreased; between 2008 and 2013, the overall ecological support increased, and in 2013 the ecological support of the midstream area exhibited the best performance  than upstream and even better than downstream area. (2) Between 2003 and 2013, the ecological pressure had been increasing, and the pressure of downstream area was the largest which surpassed that of midstream and upstream area. (3) The ecological carrying capacity decreased initially and then presented an increase between 2003 and 2013, and the upstream area showed the highest carrying capacity than midstream area and even higher than downstream area. The main factors influencing ecological carrying capacity were changed from environmental management and energy conservation to social progress and economic development. The initiatives of enhancing ecological carrying capacity have gradually changed from the elementary stage of reducing pollution emission to the advanced stage of improving environmental quality.