Abstract: Flood is one of the natural disasters causing colossal loss of life and property. It occurs with a strange regularity in different parts of India, thus devastating those particular areas. The most flood prone areas in the country are in the Ganga and Brahmaputra basins whilst the annual flood damages in the Ganga basin account for about 60 percent of the total. The extent of the damages shows a pattern of increase from west to east (downstream along the Ganga) and from south to north (towards the hills). The present study delineates the application of geographic information system (GIS) in mapping flood risk zones in Varanasi, one of the prominent districts of the Indo-Gangetic plain. The whole district witnesses havoc of flood in rainy season due to impounding of huge amount of water in the Ganga river. The damage and loss of life and cattle due to floods in the area under study are increasing year after year. It could be stated that high magnitude floods occurred in 2013 during the month of August, when the flood plains were mostly used for periodicity and gravity of food. Recognition of flooding parts and flood risk zones in the area under study are the primary steps in the flood control measures. GIS data base has been well utilized in delineating and tackling flood related problems in the area. An attempt has been made to prepare a map of an area measuring about 1526 sq. km. showing flood risk zone with the help of remote sensing data (IRS-P6, LISS III, 2008). A total of five flood risk zones are delineated in Varanasi district. With the help of remote sensing data, flood risk zones in the study area are categorized into low, middle, high, higher and highest level flood zones.