Poor waste management techniques including the indiscriminate use of poorly constructed landfills as solid waste receptors can lead to the pollution of groundwater in communities. This study examined the physicochemical qualities of groundwater proximate to a major solid waste landfill in Owerri, Imo State during rainy and dry seasons. The determination of the quality of the groundwater samples was carried out in accordance with the standards of the American Public Health Association (APHA). The results obtained from the analysis of the groundwater samples was compared to the World Health Organization (WHO) and the Nigerian Standard for Drinking Water Quality (NSDWQ) standards for drinking water. The values obtained from the analysis of the groundwater samples in both season shows that some of the tested parameters existed in values higher than both WHO and NSDWQ standards for drinking water quality. The results also showed that the concentrations of chromium, copper, iron, and nickel were above the WHO and NSDWQ standards. The Chemical Oxygen Demand, Turbidity and the Total Soluble Solids exceeded the WHO and NSDWQ standards for drinking water quality in both studied seasons. Findings from this study suggest that dumpsite solid waste could impact negatively on some physicochemical qualities of groundwater sited around their vicinity. Therefore, the location of solid waste dumpsites around residential areas should be discouraged.