Abstract:The Physico-Chemical parameters of Ulsoor Lake have been investigated. The water samples were collected from a point near the middle of the lake and analyzed for water quality parameters viz. Temperature, Dissolved oxygen, Biological oxygen demand (BOD), Chemical oxygen demand ( COD), Electrical conductivity (EC), Total Hardness, Total dissolved solids (TDS), chloride, sulphate and nitrate. The result were compared with values prescribed by WHO and other standards for drinking water quality. The pH exceeded the maximum limit of 9.0 recommended in the standards for treated wastewater. BOD exceeded permissible limit of 6 mg/l prescribed by WHO. EC exceeds the limit as per Europian standard. The nitrate levels were within the limits prescribed by all drinking water standards. All other parameters were all well within permissible limits. The water is safe based on most of the chemical parameters, the water may be unsafe due to poor microbial quality. This study was carried out from March 2011 to February 2012.