Abstract: The quasi-geostrophic adjustment process of the circulations associated with the Southern Hemisphere Annular Mode (SAM) is studied by employing the NCEP/NCAR reanalysis daily data. To SAM, which is a planetary scale system with the space scale along the latitude larger than the Rossby deformation radius, the wind field inclines to change itself so as to fit the pressure field in the process of geostrophic adjustment. The results show that the evolution of SAM lags behind the variation of the Ferrel cell anomaly about 2/16 phases, indicating the Ferrel cell changes the geopotential height anomalies in middle and high latitudes through its meridional transporting of the atmosphere mass. As the changing of the geopotential height anomalies in middle and high latitudes means the temporal evolution of SAM, SAM’s transition from positive to negative phases is demonstrated to be driven by the leading mass transportation of Ferrel cell. When the SAM changes or the meridional geopotential height gradient in middle latitudes changes, it then destroys the geostrophic equilibrium between the zonal wind field and the geopotential height anomaly in middle latitudes, causing the geostrophic deviation; then the geostrophic deviation drives the meridional wind filed, changing the anomalous Ferrel cell, and forming a self-adjustment internal process cycle.