Abstract: All life on earth depends on water. Fresh water is a critical, finite, vulnerable, renewable natural resource on the earth and plays as important role in our living environment without it life is impossible .In this paper we are analyzed to monthly variation and comparative physio- chemical study of Baba Ghat of Bihar river of Rewa city (M. P.) in March, April and May 2012. Monthly variation in physical and chemical parameters like Temperature, pH, total solids, total dissolved solids, total hardness , chlorides, calcium, magnesium, biological oxygen demand and chemical oxygen demand etc.