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With the typhoon cyclone data, NCEP/NCAR reanalysis datasets and PDO (Pacific Decadal Oscillation) index data from 1949 to 2018, the characteristics of the Violent Typhoon Event Seriously Affecting Hainan Island (VTESAH) are analyzed. Based on this, the impact of PDO on VTESAH is analyzed. The results show that the frequency of VTESAH has obvious interannual variation characteristics, with continuity and clustering. During 1960-1990, the frequency of VTESAH had a significant 8to10 year cycle, of which the 8year cycle was the most significant. There is a good correspondence between VTESAHs and cold phases of PDO, and VTESAHs are more likely to occur in cold phase years. When the PDO phase is cold (warm), there is a significant negative (positive) correlation between the frequency of VTESAHs and the sea surface temperature in the western Pacific Ocean east of the Philippines at low latitudes. When the subtropical high is weaker (stronger) and its position is farther eastward (westward) and northward (southward), the lower convergence zone shows a northwestsoutheast trend (eastwest beltshaped), and the convergence area is wider and larger (narrower and longer), it is good for the occurrence of VTESAHs in the cold (warm) phase years of PDO. The generation and development of VTESAHs can be influenced by PDO through the modulation of climate factors such as subtropical high and lowlevel circulation.