The seasonal transition of the convective (STC) in the Maritime Continent (MC) during the boreal spring can largely influence the establishment of the Asian summer monsoon, but the interannual variability of STC in MC and its causes are still not well understood. In this paper, based on the climatic characteristics of STC in MC, we define some characteristic indicators of convection and circulation, further analyze the interannual variation characteristics of STC in MC, and explore the possible effects of sea surface temperature anomalies (SSTA) in the tropics and their mechanisms. The results show that the interannual variabilities of STC in MC and the evolution of atmospheric circulation over the surrounding areas have an overall consistency, and are mainly regulated by the El Ni?o ? South Oscillation (ENSO) events. In some special years, the distribution of the SSTA in the eastern tropical Indian ocean could stimulate an anomalous local atmospheric circulation, which will ultimately lead to some changes on the convective activity in MC.