This study was conducted to investigate the concentration level of heavy metals in the water, sediment, and five fish species of the Argungu River and two surrounding lakes in Kebbi State, Nigeria. This was carried out using an atomic absorption spectrophotometer. The metal with the highest mean concentration in all fish species is Fe, followed by Cu, Pb, Cd, and Cr. The mean concentration of metals determined in the water samples ranged from 0.01 ± 0.00 mg/L to 52.52 ± 0.09 mg/L, and for sediment samples, it ranged from 0.25 ± 0.00 mg/kg to 97.70 ± 0.53 mg/kg. Hyperopisus bebe has the highest concentration of all the heavy metals analyzed. The metal concentrations in the fish samples were ranked in the following sequence: Malapterurus electricus > Alestes baremose > Clarias gariepinus > Hydrocunus brevis > Tilapia zilli. The overall concentrations of heavy metals detected in the fish, water, and sediment samples were in the following order: Fe > Pb > Cu > Cd > Cr. Fe and Pb accounted for over 90% of all the metals studied. A one-way analysis of variance (ANOVA) was employed to reveal significant differences in the measured variables. Concentrations are often lower in water, followed by sediment and fish. The results obtained indicated that the heavy metal concentrations in the fish, sediment, and water were found to be above the permissible limits set by the World Health Organization. Thus, the study revealed that there is significantly high heavy metal pollution in these fish species sampled from Argungu River and the surrounding lakes, and the consumption of the available fish species in the river may cause harmful effects to human beings.