Abstract: Under the background of deeply promoting New-type urbanization, this paper chooses Beijing-Tianjin-Hebei urban agglomeration, Yangtze River Delta urban agglomeration and Pearl River Delta urban agglomeration as the research objects to analyze the relationship between urbanization level and carbon dioxide emissions by the STIRPAT model. The results show that the relationship between urbanization and carbon dioxide emissions in the three major urban agglomerations presents a U type curve, and the relationship between the economic development and carbon dioxide emissions presents an inverted U type curve. The total population and energy intensity exert a significant positive influence on the carbon dioxide emissions, but the industrial structure has less impact on it. Therefore, the purpose of carbon dioxide emissions reduction can be achieved by accelerating urbanization process in the early phase, and by controlling the population scale and reducing the energy intensity when urbanization level reaches to a certain degree.