Based on the NCEP/NCAR daily and monthly mean reanalysis data of wind field and temperature field from 1951 to 2012, relations between the intensity of the Qinghai-Xizang Plateau (QXP) monsoon and the movement of the northern hemisphere westerlies and the causes of the location change of the westerlies were studied. The results show that the movement of the northern hemisphere westerlies is related to the intensity of the Qinghai-Xizang Plateau monsoon. The times of northward jump and southward retreat of the westerlies are the 30th pentad (1 pentad earlier), and the 59th pentad, respectively, in a year with strong monsoon, and the 33rd pentad (2 pentads later), and 63rd pentad (4 pentads later), respectively, in a year with weak monsoon. This phenomenon is also global. During the northward jump of the westerlies, the South Asian High enhances and moves northwards, the west trough of Lake Baikal enhances, and the trough within the longitude range of the QXP deepens, causing earlier northward jump time of the westerlies in a year with strong QXP monsoon, compared with a normal year. The cases are reversed in a year with weak monsoon. During the southward retreat of the westerlies, the location of the subtropical high is relatively southerly, the East Asian trough deepens. This is favorable for the south retreat of the westerlies in a year with strong QXP monsoon, compared with a normal year. The cases are reversed in a year with weak monsoon.
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