Based on precipitation from 280 meterological stations in west China and NCEP reanalysis data of OLR，the relationship between autumn precipitation anomaly and OLR in western China was analyzed using EOF，correlation analysis method．The main results are as follows:(1)The high value area of autumn OLR corresponded to the low value area of autumn precipitation，and the autumn OLR and precipitation had the remarkable opposite tendency，which indicated the increase((reduction)of autumn OLR would cause the reduction(increase)of autumn precipitation;(2)There was a large remarkable inverse correlative region between autumn OLR and precipitation in west China，especially in northwest and southeast area of west China，and in September inverse correlative area was biggest;(3)By the EOF analysis，the autumn OLR was most sensitive in the southern Xinjiang basin and northeast of Qinghai plateau，in Septemper the abnormal increase(decrease)of the autumn OLR in Turpan of Xingjiang，the autumn precipitation in southwest Xinjiang，north region of Qinghai plateau，Gannan plateau and middle Gansu was more(few)，but in the Tibet and western Sichuan plateau was few(more);In October the autumn OLR’s abnormity in west Inner Mongolia Xinjiang would resulted in remarkable inverse change of autumn precipitation in Xinjiang，north Shaanxi，north Sichuan and west Guangxi;In November the autumn OLR’s abnormity in Taklimakan desert would resulted in remarkable oppositive change of autumn precipitation in Shaanxi．The influence of OLR abnormity in sensitive area on autumn precipitation was maily in December of last year，April to June and August;(4)The low value center of OLR over the Qinghai－Tibet Plateau moved to southeast from winter to summer．In September the plateau OLR low value ascension was propitious to increase of precipitation in Tibet Plateau but decrease in the northeast side of the plateau．In October，the low value ascension of OLR was in favor of precipitation increase(reduction)in the plateau(middle Hexi Corridor)．In November both autumn OLR and autumn precipitation had no obvious correlation．The influence of OLR abnormity on autumn precipitation was maily in January，March and June．

The analysis on rainfall along the ZuliRiver valley in the past 50 years shows that rainfall decreased with latitude but increased with altitude in the northeastand southern areaswhere the altitude varies suddenly. The rainfallwas90-140mm less in an areawhich shape likes a tougue extending from northwest to southeast till the east edge in themiddle and lower area ofZuliRiver compared with otherareas. In the past50 years, the regional rainfall in ZuliRiverbasin decreased 106. 4mm on average. Waveletanalysis shows thatmore than 25 years and about10 years periods in rainfall change are remarkable.The regionalmean rainfall decreased from the late 1960s, and in 1986 it increased but after that itdecreasedmuch quickly. On the otherhand, the seasonal rainfalldistribution there was different, and itwas themost in summer, less in spring and autumn and the least inwinterwith 55%, 21% and 3% of annual rainfal,l respectively. The rainfall in autumn decreasedmuchmore in the past50 years, but it tends to increase in the beginning of this century. Influenced by human activities, rainfall there presented accelerating decrease trend because of excessive cultivation in themiddle and lower region andmany smallwater conservancies in the upper of the river. The rainfalldecreased slowlywhere vegetation cover increased and human activities influenced less on land surface.