Abstract: The Beijing Climate Center atmospheric general circulation model version 2.1 (BCC_AGCM2.1, or simply BCC) developed by National Climate Center (NCC) is applied to investigate the stratospheric zonal circulation, upper level jet, polar vortex and stratospheric sudden warming (SSW) events. The comparative analyses of the simulative results with the ECMWF and NCEP reanalysis data show that the BCC_ AGCM2.1 simulations forced by the observed sea-surface temperature, CO2 and aerosol can reproduce the observational characteristics in the distributions and seasonal cycles of the stratospheric zonal mean wind and temperature. The main differences between the reanalysis data and the simulated temperature profiles and upper level jets appear in the middle and high latitudes of the southern and northern hemisphere winter. The simulated stratospheric temperature is generally colder than that of observational results, and the obvious biases exist in the tropopause regions and the stratospheric upper levels. On the other hand, in the simulation results, the upper tropospheric subtropical jet locates a little southward with weaker intensity, while the stratospheric polar night jet is closer to the polar areas and stronger than the reanalysis data. These distribution features of westerly jets lead to a stronger equatorial waveguide of planetary waves in the model, and the intensity of simulated planetary wave is weaker than that in reanalysis data. Therefore, the polar vortex in the model is much more stable and has lower temperature in the polar regions in northern hemisphere winter. In addition, the model is also able to reproduce the seasonal cycle of polar vortex, but with a bad simulation about the stratospheric sudden warming events happened in northern hemisphere winter. There are some differences between the simulation results and the reanalysis data about the SSW processes, including the frequency of warming occurrence, the triggered time and warming intensity. These results demonstrate that there is still a lot of work to do to improve the simulation ability of our BCC model.