The rapid process of urbanization worldwide has a profound effect on global carbon cycle.It's important to have an explicit understanding of the spatial distribution of CO_2 to recognize and control Green-house gases(GHGs)emission,which is helpful to reduce human-induced contribution to global climate change.The study area of this project is set in the metropolitan city of Shanghai with the background of high-intensity of human activities and rapid urbanization.Mobile measuring methodology was used to determine near surface CO_2 concentration along typical transects in spring,2014 by means of near infrared gas analyzer LI-840A,combined with classification of urbanization levels and types of land use information derived from remote sensing data.Qualitative and quantitative analysis of CO_2 concentration's response mechanisms to urbanization levels and types of land use are represented in this paper.Data suggested a well-shaped carbon dioxide dome with mean concentration of 445.840.5mumol/ mol in the city center,55.1mumol/mol(13.3%)higher than that in suburban areas.CO_2 concentration exhibited a significant spatial heterogeneity and descended in a sequence with three directions which were northwest,southwest and southeast,respectively.Near surface CO_2 has a negative relationship with distance to the city center with a decline of 1.56mumol/mol per kilometer.In general,Near surface CO_2 concentrations dropped rapidly within the range of 20 km from the urban core(DUC)while rather slowly out of the same range(approximately 0.7mumol/mol/km).Urbanization levels within the territory of Shanghai City have significant impacts on concentrations of near surface CO_2.According to the classification of urbanization levels,concentrations with high,middle,low urbanization level and suburban areas are 467.644.7,451.741.1,452.734.9 and 426.024.8mumol/mol,respectively.Coverage rate of forested land has the highest correlation with near surface CO_2 concentration following by the construction areas,farmland and grassland with the correlation coefficient of-0.64,0.63,-0.55 and -0.52(P<0.01),respectively.Correlation coefficients between near surface CO_2 concentrations and types of land use score higher values in high urbanization and suburban areas than in middle and low urbanization areas.