Abstract: In this study, the CO₂ emission characteristics and its relationships with C and N concentration in soil amended with different types of residues were studied by thermostatic incubation method to investigate the decomposition characteristics of different types of residues after adding to the soil and the effect of C, N concentration in residues on carbon sequestration. The results showed that during 61 days incubation, the CO₂ efflux rates in the soils added with the different residues changed over time and exhibited an initial decrease, followed by a stable low plateau, and then an increase to a high plateau and finally followed by a decrease. The characteristics of CO₂ emissions varied with residues, with the differences mainly occurring in the starting and duration of the high plateau CO₂ emission period. The cumulative CO₂C emission was significantly affected by residue type. The cumulative CO₂C emissions from soils amended with corn roots, bottom corn stalks, corn leaves, and soybean leaves (about 160 μmol·g^-1 of soil and residue) were significantly greater than those from soils amended with other residues for the initial 21 days. Except for soybean leaves, the cumulative soil CO₂ emissions over the 61 day incubation period from soils amended with soybean residues were higher than that from soil amended with corn residues. There were significant linear relationships between the ratio of cumulative CO₂C emission to residue carbon concentration (CR), and both C/N and nitrogen concentration of residues in the initial 21 days incubation, but not for the entire 61 days incubation. Our study suggested that soil CO₂ emission was closely dependent upon the type of residue. Soybean residues decomposed more easily than corn residues. However, the decay rate of soybean residues was slower than that of corn residues at the initial stage of incubation. Soil CO2 emission was significantly affected by the C/N ratios and nitrogen concentrations of crop residues only at the early phase of incubation.