Asian summer monsoon (ASM) is a key pathway for the tropospheric water vapor and pollutants transporting into the global stratosphere and these chemical species will have great impact on stratospheric ozone layer and global climate via microphysics, chemistry and radiation processes, which is a hot topic for international scientific community. Tibetan Plateau has a great impact on the atmospheric circulation owing to its giant terrain and strong summertime heat source, and takes an important role in the stratosphere-troposphere exchange. Currently, there are many uncertainties in the understanding the vertical distribution and variation of chemical species in the upper troposphere and lower stratosphere (UTLS) during the ASM, stratosphere-troposphere exchange processes and its contribution to the budget of chemical species in the global stratosphere, among which, lack of chemical species measurement (particularly in situ observation) is a critical limitation. In this project, combination sounding of water vapor, ozone and particle will be conducted during the ASM as a priority task. The spatial distribution and variability of species in the UTLS will be analyzed by investigate the sounding data combined with satellite product. Numerical simulation and diagnosis will be conducted to explore the transport processes during the tropospheric pollutants into stratosphere. Finally, the contribution of stratosphere-troposphere exchange during the ASM will be assessed in the budget of species in the global stratosphere. These studies will provide evidence and physical bases for further investigation of the global climate effect of the ASM stratosphere-troposphere exchange.