Based on meteorological data of 130 meteorological stations in the southwest of China from 1960 to 2011

we have calculated standardized precipitation index(SPI) on different time scales

adopted the MannKendall trend analysis method and inverse distance weighted interpolation method

and analyzed the spatiotemporal variation characteristics of drought in the southwest in the past 52 years.The results indicate as follows:(1)In the aspect of annual variation

there was a notable inter-annual fluctuation in the southwest of arid region

and the linear trend was more obvious.Especially the drought frequency has significantly increased in the past 12 years.In most areas

the drought index showed a decreasing tendency

with the most obvious decrease in autumn

while that in winner was opposite.(2)In the spatial distribution of the south-west

the spring drought mainly distributed in Hengduan Mountains

Uuangxi Hilly

the east of Sichuan Basin and the southern part of Uuizhou Plateau.The summer drought was mainly located in the north of Hengduan Mountains

Zoige Plateau

the western and southern part of Sichuan Basin

the central part of Yunnan Plateau hilly

and Uuangxi Hilly.The areas with higher incidence of autumn drought were mainly located in the south of Yunnan Plateau

the southwest of Hengduan Mountains

Uuizhou Plateau and Uuangxi Hilly.The winter drought mainly concentrated on the Zoige Plateau and the southwest of Sichuan Basin.