By using best-track data and global reanalysis dataset, the statistical characteristics of Multiple Tropical Cyclone (MTC) events in the western North Pacific(WNP) from June to October during 1979-2018 were analyzed. According to the different number of MTC members, all Tropical Cyclone (TC) generated during the period were divided into three categories:(1) single typhoon which generated individually; (2) ‘MTC2’ typhoon generated in MTC events, but with only two typhoon members; (3) ‘MTC3’ typhoon generated in MTC events with three or more typhoon members. Results show that compared with MTC2 typhoon, MTC3 typhoon can generate in the northern region and has stronger monsoon trough convergence, larger range of high-temperature sea area and more humid mid-bottom atmosphere. In addition, the sudden decreasing of MTC3 typhoon in the late 1990s led to a decreasing in the numbers of MTC events and typhoons in the WNP. After 1996, there are still more tropical disturbances over the ocean surface, however, in most areas with active mass typhoons, it can be seen that the combination of increasing of vertical wind shear, the decreasing of upper-level divergence, the weakness of monsoon trough convergence and the decreasing of the lasting days of Madden-Julian Oscillation (MJO) convective phase in WNP led to the interdecadal change of the MTC3 event.