An analysis of the relationship between the genesis of the tropical cyclones over the western North Pacific and the interannual variation of the global atmospheric circulations as well as the northern edge of the Antarctic sea ice was made by using the grid wind data during 1973-1981,1980-1986 and the Antarctic sea ice data during 1973-1978 as well as the conventional data.The results show that over the region of the Eastern Hemisphere the annual frequency of the tropical cyclones of the two Hemisphers is connected closely with the intensity of the cross equatorial flow (Eastern Hemisphere), particularly with that at 40°E. At the same time, it is closely connected with the interannual variation of the northern edge of the Antarctic sea ice.When there is a "warmer winter" and a "colder summer" in the Antarctic,there will be a higher annual frequency of the tropical cyclone over the western North Pacific.