This study aims to analyze hydrological effects of water reservoirs on hydrological processes using SVM, MRL and ANN techniques. The results indicate that: 1) ANN model performs well in handling hydrological processes under the influences of human activities, the construction of water reservoirs in this study, and climate changes. The ANN model is accepted as the right model for the hydrological simulations. 2) Generally, two time periods can be identified with different influences of water reservoirs within the East River Basin: 1974- 1982 is characterized by insignificant hydrological alteration and influences of hydraulic facilities are minor; the period of 1983-2000 is dominated by significant alterations of hydrological processes with influences of water reservoirs on hydrological processes, and the result is to flatten the fluctuation of hydrological processes. 3) The hydrological processes of the Longchuan, Lingxia and Boluo stations are heavily influenced by hydrological regulations of water reservoirs with different influences: Boluo station is heavily influenced by hydrological regulations of water reservoirs and is followed by Lingxia and Longchuan stations. Besides, the monthly streamflow changes are subject to flattening processes under the influences of water reservoirs.