The Tibetan Plateau is an important channel of water vapor and pollutants from troposphere into stratosphere, and these atmospheric constituents have important impact on the global climate. By using MLS and ERAInterim data, the distribution of atmospheric composition, including H2O, O3, CO, and IWC during a strong convective weather process occurring in the central Tibetan Plateau is analyzed. With the Wei formula to estimate the H2O and O3 flux crossing tropopause. Results indicate: (1) O3 mixing ratio increased from 03×10-6(V) ppmv to 09×10-6(V) at 100 hPa compared with the average; CO increased 08×10-6(V) below 150 hPa; H2O by 80 ppmv at 215 hPa and IWC significantly increased more than double to 0027 g/m3 (2) Before the convective activity began, the upward movement gradually strengthened, and total O3 and H2O flux were contributed by the vertical instantaneous movement. Thus the lifting effect of the strong convection to the atmosphere in UTLS (Upper Troposphere and Lower Stratosphere) made atmospheric composition change accordingly over the Tibetan Plateau.