Based on monthly precipitation data from Delingha weather station during the period of 1956-2013, the drought was characterized by means of standardized precipitation index (SPI)， and this paper analyzed the different temporal scale variation characteristic of precipitation and drought by using the methods of linear trend, Mann-Kendall trend test and abrupt change check, sliding t-test, Morlet wavelet transformation, R/S analysis and standardized precipitation index. The results indicated as follows: Rainfall was below normal level before 1980s, and was above normal level after 1980s, showing an upward trend. The winter precipitation variation was relatively stable. Precipitation in autumn experienced a great fluctuation. Annual and seasonal precipitation showed a significantly increasing trend in recent 60 years. The increasing rate of annual precipitation was 21.16 mm/(10a), the trend of summer precipitation was the most obvious, and its increasing rate was 12.35 mm/(10a). There were not only the 3-9a short-term periodic changes of annual and seasonal precipitation, but also the 18-28a longterm periodic changes. Correlation analysis shows that SPI and Rainfall anomaly were significantly correlated and there was a downward trend in drought severity, two periodic oscillation of droughts were found，including 5a period and 18a period. There was a continuance for precipitation in Delingha weather station of Bayin River basin, in the future, it will maintain an increasing trend, and however, the drought severity will keep a downward trend.