Based on the satellite data of moisture and temperature from AURA/MLS,the cloud physical information from CALIPSO/CALIOP,and the reanalysis dataset of ECMWF/Interim,this paper studies the distribution of cloud top above the tropopause(CTAT) events and its effect on water vapor and temperature structures in the upper troposphere and lower stratosphere(UTLS) over East Asia.Results are as follows:1)The maximum frequency of CTAT(reaching 30%-55%) in boreal summer is located in Asian monsoon region.Meanwhile,the maximum frequency of CTAT in the mid-latitudes is located in Northeast Asia,exceeding 15%-20%.2)Based on the CTAT,the composite analysis suggests that there is an anomalous structure of "dry above-moist below" and "cold above-warm below" in UTLS along 15-35°N over East Asia-West Pacific,which is consistent with the composite analysis result based on the tropical cyclones.It means that the tropical cyclones are the main weather systems forming CTAT in this area.3)The composite analysis shows that there is an anomalous structure of "dry above-moist below" and "warm above-cold below" in UTLS along 35-50°N over Northeast Asia,which is consistent with the composite analysis result based on the extratropical cyclones,meaning that the extratropical cyclones dominate the formation of CTAT there.