Changes in the frequency of typhoon occurrence and landfall location in the East China Sea are investigated by using the best typhoon track data in Northwest Pacific Ocean from 1951 to 2015.This 65-yr record is provided by Japan Meteorological Agency(JMA).This paper focuses on the East China Sea region,investigating typhoon frequency,landfall position,the relationship between typhoon occurrence(landfall position) and the Pacific Decadal Oscillation(PDO) and El Niño/La Niña and Southern Oscillation(ENSO),and the possible factors affecting typhoon generation and movement.The results indicate that:(1)July-August-September is the season of the highest occurrence for typhoons in the East China Sea,with the highest number of typhoons occurring in August.Typhoons making landfall in this region have similar behavior.(2)The occurrence of typhoons entering the East China Sea has both interannual and interdecadal trends.During the PDO warm(cool) phase,fewer(more) typhoons occur and the occurrence shows an upward(downward) trend.Fewer(more) typhoons enter the East China Sea during El Niño(La Niña) periods.Niño3.4 index and typhoon frequency show a negative correlation as a whole,with the correlation coefficient of -0.32 at 90% confidence level.(3)The latitude of the typhoon landfall point varies greatly,ranging from 24 to 36°N.A certain interdecadal change is also observed.During the PDO warm(cool) phase,the typhoon landfalls are further north(south) and have a tendency to move northward(southward).However,the relationship between typhoon landfall latitude and ENSO is relatively complex and needs further investigation.(4)The primary reason for the change of the typhoon occurrence and landfall may be attributed to the location and strength of the subtropical high in Northwest Pacific.During the PDO cold(warm) phase,the Northwest Pacific subtropical high weakens(strengthens) and the subtropical high moves in an eastward and northward(westward and southward) direction.Under the condition of a strong(weak) tropical convergence zone over Northwest Pacific,this kind of atmospheric circulation contributes to the generation of typhoon,leading to the high(low) frequency of typhoons entering the East China Sea and the further north(south) typhoon landing point.