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Pollution of surface water and sediments with heavy metals continue to cause ecological threat around the globe. The objective of this study was to examine the physiochemical parameters of Owena River and to assess the concentrations of heavy metals in the river and sediments. The heavy metals investigated in both water and sediments were iron (Fe), lead (Pb), chromium (Cr), cadmium (Cd), zinc (Zn) and arsenic (As). The observed metal concentrations were subjected to pollution indices contamination factor (CF), Geo-accumulation (Igeo), potential ecological risk index (PERI) and potential toxicity response indices. Surface water and sediments samples were collected in triplicates and transported to the laboratory for analysis. Physicochemical parameters were checked in-situ using the water multi-parameter probe. The result showed that all examined physiochemical parameters were within the World Health Organization’s (WHO) limits. The concentrations of examined heavy metals in the river were within the limits except for Zn (1.13±0.006-2.14±0.000mg/l) and Cr (0.19±0.005-0.34±0.006mg/) while that of Fe, Cd, Zn and Cr in the sediments were observed to be higher than the permissible limits. The CF values ranged from moderate and to very high, Igeo showed not contamination and PERI revealed low level. This study recommended that due to the high concentrations of heavy metals found in the sediments, regular and close monitoring of discharges from domestic, agricultural and industrial effluent, solid waste disposal and defecation actives should be reduced. Keywords: potential ecological risk, heavy metals, contamination factors, geo-accumulation index, sediments