The study was undertaken to find out the effects of chronic consumption of oxidized palm oil on renal handling of Na+, K+, Cl-, HCO3- in Wistar rats. Twenty four male wistar rats weighing 140-160 grams at the begining of the experiment were randomly divided into four groups namely: control, fresh palm oil diet fed (fed 15% w/w fresh palm oil), photoxidized palm oil diet fed (fed 15%w/w photoxidized palm oil), thermoxidized palm oil diet fed ( fed 15% w/w thermoxized palm oil) groups. All four groups received water at libitum. At the end of twelve weeks, urine and blood samples were collected for the analyses of the concentration of Na+, K+, Cl-, HCO3-. Results showed that Plasma Na+ and Cl- concentrations in the TPO and PPO groups were significantly lower than the control (P<0.001) groups and FPO (P< 0.001 and 0.01 respectively)groups. Their (TPO and PPO) Na+ urine concentrations were however significantly (P<0.001) higher than the control and FPO. K+ plasma levels on the other hand, were significantly higher in the TPO (P<0.001) and PPO (P<0.05 and P< 0.01respectively) groups when compared with the control and FPO; but significantly (P<0.001 and P<0.01)lower in the urine. Plasma HCO3- concentration in the TPO group was significantly (P<0.01) lower than the control, FPO and PPO groups while that of PPO was significantly (P<0.05) lower than FPO. Urine K+ concentration of TPO was significantly(P<0.001) lower that the control and FPO while PPO levels were significantly (P<0.05) lower than the FPO only. In conclusion, chronic consumption of oxidized palm oil causes hyperkalemia, hyponatremia and hypobicarbonatemia.