Total ozone from July 2009 to December 2013 measured by Total Ozone Unit (TOU) borne on the FY-3A meteorological satellite is validated with the ground-based observations over the global five latitudinal bands, the north pole (north to 63.5°N), middle north of hemisphere (23.5°N～63.5°N), tropic zone (23.5°N～23.5°S), middle of south hemisphere (23.5°S～63.5°S) and South Pole (south to 63.5°S). The results show that the linear correlated coefficient between TOU and the ground-based data is more than 0.95. The globally average TOU Relative Difference (RD) from the ground-based data is (-0.16±4.3)%, with the respective of (0.6±3.8)%, (-0.5±3.9)%, (1.8±3.1)%, (-0.6±3.7)% and (-0.1±3.9)% over the 5 north-southward bands. The sensitivity tests suggest that TOU RD over the tropical zone evidently rises with the growth of the ground-based total ozone. The global TOU ozone RD reduces as the Solar Zenith Angle (SZA) is greater than 70° and the RD may reach from -4% to -10% as SZA from 75° to 85°. The TOU ozone RD is insensitive to the variability of cloud amounts and altitudes: the RD ranges within ±2% as the cloud amount changes from 0 to 100% or the cloud altitude changes from 1 to 15km. The TOU ozone RD is sensitive to the absorptive aerosol characterized by the positive Aerosol Index (AI), and it may decrease from -2% to -5% over the middle of south hemisphere as the AI from 1 to more than 2. The globally respective RD of TOU ozone to Dobson, Brewer and SAOZ observations is (0.6±0.17)%, (0.05±0.2)% and (0.04±0.01)%. TOU RD is generally negative as the Dobson or SAOZ total ozone is lower than 200DU, while it generally 2%～6% as SAOZ total ozone is 430～500DU. The respective RD of TOU to Dobson, Brewer and SAOZ is also insensitive to variations of SZA (less than 70°) or the cloud amounts, however, the RD of TOU respective to Brewer and SAOZ may behavior some small trend with the occurrence of high cloud or positive AI.