The present study aimed to investigate the protective effect of ascorbic acid on paraquat induced serum biochemical alterations in experimental rats. Forty-eight (48) male albino Wistarrats were randomized into four (4) groups consisting of twelve (12) in each. Group 1- Control. Group 2 ? Paraquat at the rate of 40 mg/kg b.wt. Group 3 ? Ascorbic acid at the rate of 250 mg/kg b.wt. Group 4 ? Paraquat at the rate of 40 mg/kg b.wt + Ascorbic acid at the rate of 250 mg/kg b.wt. The treatment regimens were administered by oral gavage once daily for twenty-one (21) days. Significantly (P<0.05) increased activity of aspartate transaminase, alanine transaminase, alkaline phosphatase, blood urea nitrogen and serum creatinine and significantly (P<0.05) decreased activity of total protein was observed in group 2 on 7th and 21st day of experiment. Co-treatment with ascorbic acid showed a remarkable protection against the parameters investigated possibly via antioxidant defence mechanism.