Abstract: This paper introduces the conception of GIS and the state of GIS applicadons to the hydrology and the water resources management, and summarizes and reviewes the applications of GIS to the hydrology and the water resources management by means of a number of examples including the data management, hydrological modelling, water resources and environment management, and applications of advanced technique and theory.A ccording to there are existed problems in the applications and the prospects of computer technique and information technique some suggestions are proposed to apply GIS to the hydrology and the water resources management in the future.