Based on the data from the 16 meteorological stations around alpine grassland nature reserves (Kekexili, Qiantang, Aejinshan), we analyzed the regional temperature and precipitaton trends from 1957-2011 using the daily precipitation data. The results showed that, in the past 55 years, the annual maximum, minimum and average temperature increased significantly. Mann-Kendall method showed the increasing trend exhibited a very significant level and the temperature growth rate was 0.71°C/10a. By comparing three methods including regional average method, linear regression mthod and exponential model for simulating precipitation change, we found that linear regression model had a higher value, exponential model had the largest variations and regional average method was lower than the linear regression model. Exponential model can well fit the relationship between preciptiation and elevation. In general, there were large fluctuations of the annual average precipitation. Precipitation showed increasing trend in 1960s and decreasing trend in 1970s Overall, there was a significant increasing trend based on Mann-Kendall analysis. Also, SPEI index which was integrated precipitation and temperature was used to analyze the drought dynamics and Kriging interpolation to reveal the spatial differences of three nature reserves. SPEI index showed that the climate in these nature reserves had a trend from dry to wet condition. The average annual precipitation, temperature and variations varied greatly among the three grassland nature reserves. The average annual temperature values for Kekexili, Qiangtang and Aerjinshan nature reserve are 1.9, 15.4 and 6.0°C and precipitation values are 261, 141 and 107 mm/a. In summary, we analyzed the dynamics of climate change based on SPEI index, and spatial variability of temperature and precipitation. The results provide basis for nature reserve management.