In the  present work, characterization of leachate from an open dumpsite, Jawaharnagar, Rangareddy district, Telangana and its effects on surrounding ground water was investigated. A total of one leachate sample and twelve ground water samples were collected during pre-monsoon and post-monsoon seasons(2015) for monitoring purpose. All the samples were analyzed for physico-chemical parameters(pH, TDS, TH, CH, Cl^-, SO₄^-2, NO₃^- and F^-) as per standard procedures(APHA). Results indicate that, only pH and sulphates were found to be within the permissible limits in ground water recommended by WHO:2006. Total dissolved solids, Chlorides and Nitrate levels were found to be alarming in both pre and post monsoon. Water quality index(WQI) study also showed that most of the water samples fall in “Poor” and “Unsuitable” category. It is evident that the leachate from the municipal dumpsite is polluting the ground water at greater extent making them unsuitable for drinking purpose. Therefore, immediate measures should be taken to control the leachate contamination in the ground water.