Global warming has increased the intensity and frequency of extreme precipitation events. Indochina Peninsula and South China (INCSC) is located in the monsoon region and thus is vulnerable to extreme precipitation with flood disaster. Using daily precipitation data, this paper objectively classified the extreme precipitation events in the INCSC region during the wet season (May to October) over 1951 to 2015. The circulation characteristics and interannual, interdecadal and long-term trend characteristics of each extreme precipitation cluster were analyzed. The results suggest that (1) According to the location of precipitation center, the extreme precipitation in the INCSC region can be objectively grouped into South China, Indochina Peninsula, Burma–Yunnan, and Southern South China–Northern Vietnam clusters. The associated large-scale meteorological patterns (LMP) are characterized by mid-high latitude wave trains and tropical dipole circulation. The LMP of the South China cluster features a "+ ? +" meridional wave train in the upper troposphere, which bears some resemblance with the East-Asia Pacific (EAP) teleconnection pattern. However, the centers of LMP lie southwestward to the EAP counterparts. The negative anomaly circulation in central East China is the key system. In the lower troposphere, LMP features a "+ ?" meridional wave train located at low latitudes. The LMP of the Indochina Peninsula cluster features a dipole anomaly circulation of enhanced monsoon trough and Mascarene high pressure in the upper to lower troposphere. The LMPs of the other two clusters of extreme precipitation have a combination of Rossby wave train in the upper troposphere and the moderate tropocial diople in the lower troposphere. (2) The occurrence of extreme precipitation days in the INCSC region exhibits a significant upward trend, which is contributed by the South China and Indochina Peninsula clusters. The occurrence frequence of meridional wave-train LMP increased the extreme precipitation days in the South China cluster. (3) The extreme precipitation of Indochina Peninsula and South China clusters are antisymmetric with each other. From the perspective of the Indochina Peninsula cluster, the maintenance of low pressure elongating from the Arabian Sea via Indochina Peninsula to South China Sea is unfavorable for the occurrence of extreme precipitation in South China.