<p>B vitamins have been reported to exert therapeutic effects in different models of chemical induced toxicity and organ damage. The present study aimed to investigate the ameliorative effect of vitamins B1, B6 and B12 on aluminium chloride (AlCl₃)-induced oxidative stress in the liver, kidney and heart in Wistar rats. Thirty rats were randomly distributed into five groups of six animals each. Group 1 served as the control, group 2 received AlCl₃ (100 mg/kg/day) only throughout the study. Groups 3, 4 and 5 were treated with 5 mg/kg/day of vitamins B12, B6 and B1, respectively, in addition to 100 mg/kg/day AlCl₃. All treatments were administered orally and lasted for 40 days. Standard methods were used to evaluate the activity of superoxide dismutase and levels of reduced glutathione, nitric oxide and malondialdehyde in the liver, kidney and heart of rats. The activity of sodium–potassium ATPase (Na/K ATPase) was also estimated in the heart and kidney homogenates. The activity of creatine kinase and lactate dehydrogenase, as well as level of troponin I were estimated in the heart homogenate. Results from this study indicated that treatment with Vitamins B1, vitamin B6 and vitamin B1 ameliorated the deficits in antioxidant defence system, lactate dehydrogenase, creatine kinase and Na/K ATPase activity. These observations were corroborated by results of histopathological evaluation. It can be concluded that the vitamins protected the tissues examined against AlCl₃-induced oxidative damage. Moreover, no significant difference was observed in the protective abilities of the vitamins.</p>