Land use changes alter the hydrological characteristics of the land surface, and have significant impacts on hydrological cycle and water balance. Therefore, it’s very important to study hydrologic response of land use changes for analyzing the complex effects of human activities on natural systems and improving water resource management and flood control. The distributed hydrological model is the key tools that can be used to give insight in the hydrological impacts of land use changes. This paper selects Taihu Basin as study area, with high-speed urbanization. Historical iand use scenarios for 1985, 1995, and 2000 were analyzed to track land use change by TM/ETM image explanation and spatial analysis of Arcgis software. The STREAM model, a cell-based distributed hydrological model, was applied to estimate hydrological response of land use changes by simulating the monthly and annual runoff using long-term rain records from 1980 to 2000. For the entire basin between 1985 and 2000, the urban area increased about 40.38%, about 3.88% of the whole basin area. The land use changes result in an increase of 7.56 x 10⁸m³ on average and 10.0 x 10⁸m³ on maximum, about 4.11% and 11.76% of the whole basin runoff volume respectively. Hydrological response varies according to the extent of land use changes in different parts of the basin. In Suzhou-Wuxi-Changzhou and Pudong-Puxi sub-region, with more extent of land use changes, the land use changes result in an increase of 10.07% and 7.03% respectively on average, and 20%-30% on maximum.