Abstract: Urban land use is an important driving force of social and economic development as well as one of the important factors affecting carbon emission. Based on the analysis of 15 sub-provincial cities in China, the panel regression model was used to analyze the carbon emission efficiency of these cities from 2001 to 2017, the results indicate that:(1)From 2001 to 2017, the carbon emission efficiency of each sub-provincial city showed an overall upward trend, with an average growth rate of 6.823%. Chengdu had the most significant upward trend, whose average annual growth rate is 13.150%，Shenzhen had a slow average annual growth rate of only 5.232%.(2)The intensive use of industrial land (IILU) has a significant impact on the urban carbon emission efficiency. The per capita labor force, capital investment, science and education expenditure have a significant positive effect on carbon emission efficiency, while the per capita energy consumption has a negative effect. In the controlled variables, except that the influence of urbanization is insignificant, the proportion of industrial output value and per capita GDP have a significant promoting effect on carbon emission efficiency, while sulfur dioxide emission per unit of industrial output value has a significant inhibiting effect.(3) Different explanatory variables in the IILU index have different effects on the different areas with low, medium and high carbon emission efficiency. The regional differences are quite large. The factor of per capita labor force only has a positive effect on the area with high value, the factor of per capita energy consumption has a significant negative effect on the area with low, medium and high value, the factor of per capita capital has a significant promoting effect on the area with low, medium and high value, and the factor of per capita science and education has a significant promoting effect on the area with low, medium and high value. The research proposes countermeasures and suggestions from the aspects of improving land conversion rate, changing extensive economic development mode and advocating green development path of low-carbon civilization, so as to reduce urban carbon emission, environmental pollution and achieve the purpose of optimizing urban air quality.