Groundwater is the largest source of usable fresh water in the world. A special significance is emphasized on study of groundwater quality for drinking, industrial and domestic water supply. Most of the population of Udupi district completely depends on groundwater for their drinking, domestic and irrigation purposes. Hence, in this study, about 35 bore-well water samples were collected from 35 different wards of Udupi municipal area. For each groundwater sample, about 26 water quality parameters, such as pH, electrical conductivity (EC), total dissolved solids (TDS), total hardness, total alkalinity, sodium, ammonium, potassium, magnesium, calcium, fluoride, chloride, nitrate, sulphate, phosphate, hydroxide, bicarbonate, carbonate, copper, chromium, manganese, iron, cobalt, nickel, cadmium and lead were determined. Conductivity and pH meter were used for the analysis of pH, electrical conductivity and total dissolved solids. Titration was used for analysis of total hardness and total alkalinity. Ion chromatography method was used for analyzing groundwater samples for cations and anions. Whereas, atomic absorption spectrometer was used for the analysis of groundwater samples for heavy metals. The study aims at studying the hydrogeochemical relationship of groundwater using Piper's trilinear diagram and understanding the suitability of groundwater for drinking and irrigation purposes. Also, ArcGIS-9.2 software was used to represent the spatial distribution of water quality index in the study area.