This study was carried out to investigate the impact of poor waste management on the physicochemical properties of ground water in Ibadan which will be reflected in the extent of contamination of wells in order to establish its suitability for drinking. Twenty samples of ground water (well), collected from five local governments in Ibadan were analysed for colour, temperature, pH, total solids, total dissolved solids, total suspended solids, total hardness, magnesium hardness, calcium hardness, chloride, alkalinity and dissolved oxygen using standard methods. The ranges for temperature, pH, total solids, total dissolved solids and total suspended solids were 23-30°C, 4.57-6.55, 124.5-1585, 40.5-1490 and 30-270 mg L-1, respectively. While that of total hardness, magnesium, calcium, chloride, alkalinity and dissolved oxygen were 22-202, 2-60, 20-186, 20-510, 30-430 and 2.34-7.11 mg L-1. Fifteen of the water samples were colourless and the others were turbid. The results obtained for pH (95%), Magnesium (25%), Chloride (20%), Alkalinity (55%), all exceeded the W.H.O maximum permissible limits, indicating that some of the groundwater samples in Ibadan city were contaminated to various extents probably from lack of proper waste management.