The study is devoted to the structure of low-frequency dipole of the East-Asian westerly jet entrance and exit regions and to the characteristics of Asian/Pacific low-frequency vortex activities in terms of the bandpass filter for 30-60 days and composite technique and with the 1984—85 winter ECMWF grid data. Results show that the low-frequency cycle of the zonal wind dipole is accompanied by the east-west shift of the eastern Asian westerly jet core and low-frequency meridional circulation at the jet entrance is important to the oscillation in zonal wind. NW-SE wavetrain runs from Ural to mid Asia and then to East Asia and the low-frequency vortices of Ural origin travel southward and then eastward,leading to the change in phase of the wavetrain. Over the central Pacific there is a meridional wavetrain and the counterclockwise loop of the couple of cyclone and anticyclone gives rise to the change in the low-frequency wavetrain in this area.