The radiation emission of CO 2 plays an important role in the radiative heat transfer of high-temperature furnace and gas turbine, it is essential to estimate the radiative heat transfer of CO 2 accurately with an appropriate spectral database. Based on the two versions of high-resolution transmission molecular absorption databases (HITRAN 2008 and HITRAN 2016), the latest version of high-temperature molecular spectroscopic database (HITEMP 2010) and the high-temperature version of carbon dioxide spectroscopic databank (CDSD-4000), the statistical narrow band (SNB) model was employed to study the radiative heat transfer of CO 2 in a one-dimensional planar enclosure. The effects of four different spectral databases on accuracy of radiation calculation results of CO 2 were discussed. The results calculated with CDSD-4000 database were in good agreement with the benchmark, and the maximum average relative error was 6%. Moreover, the absolute values of the radiative heat source calculated with CDSD-4000 in all cases were larger than the benchmark, because there were more spectral lines involved in CDSD-4000 database. However, due to the lack of hot lines in HITRAN databases, significant deviation could be observed, especially for the high temperature cases with 39% maximum average relative error. Finally, the Planck mean absorption coefficients of CO 2 were calculated by the LBL method with CDSD-4000 database.