Abstract: In order to analyze and assess the impact of climate change on regional hydrology and water resources, three indices including average annual precipitation,the trend index and Hurst coefficients reflecting the continuity of hydrology series are calculated on the bases of measured annual precipitation series in the east of China from 1956 to 2000,and then compared with those calculated on the bases of the simulated annual precipitation series from each of three climate models(CGCMA3,MPI-ECHAM5 and Average GCM).It is found that each index values between the observed and simulated series are different quantitatively and even contradictory qualitatively.This indicates that the uncertainty is significant in the application of models.Similarly,average annual runoff,the trend index and annual runoff of different drought years for the future annual runoff series from 2001 to 2050 also have significant uncertainty. Future annual runoff series is produced by using the predicted annual precipitation and temperature data from three climate models.Finally,some suggestions on climate models and its application are proposed in this study.