Paracetamol is a harmless antipyretic and analgesic at the therapeutic dose, but when used by overdose cause hepatic damage. The study was planned to evaluate the effect of cinnamon extract on paracetamol-induced liver injury in rats. Thirty male rats were allocated into six equal groups, control group, silymarin group cinnamon group, paracetamol group, cinnamon + paracetamol group and silymarin + paracetamol group. At the end of experiment, blood and liver tissue samples were collected. Paracetamol caused rise in liver enzymes including alanine amino transaminase (ALT), aspartate amino transaminase (AST) and alkaline phosphatase (ALP), with changes in protein and lipid profiles. It also caused hepatic lipid peroxidation with decreasing the activities of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD). Pretreatment with cinnamon extract for 30 days improves the adverse effects of paracetamol evidenced by biochemical and histopathological findings. In conclusion, cinnamon extract can serve as a hepatoprotective agent against paracetamol-induced liver damage.