Lead is one of the ubiquitous environmental pollutants that induce a broad range of physiological and biochemical dysfunctions in animals. This study evaluated the effects of dietary lead exposure and ascorbic acid on performance, serum biochemical parameters, plasma malonclialdehyde and lead accumulation in broiler chickens. For this purpose, lead acetate at 200 mg/kg and ascorbic acid at 100 mg/kg were added to the diet alone or in combination for 42 days. A total of 120 broiler chicks were divided into 4 treatment groups: control, ascorbic acid, lead, and lead + ascorbic acid. By the end of the study, lead caused body weight and body weight gain to decrease significantly, although its effects on feed consumption and the feed conversion ratio were not significant. While lead did not alter the serum lactate dehydrogenase, aspartate aminotransferase or alanine aminotransferase activities or albumin or total protein concentrations, it increased malondialdehyde (P < 0.001) and triglyceride (P < 0.01) levels. Although the lead contents of the serum and muscle were unchanged, lead was accumulated in the liver and kidneys (P < 0.001). Our results showed that lead (200 mg/kg diet) had an inhibitory effect on the growth of broilers and appeared to be inducing lipid peroxidation. The addition of ascorbic acid to the diet reduced the plasma malondialdehyde levels induced by lead and tended to reduce the inhibitory effect of lead on growth. It is concluded that the addition of higher doses of ascorbic acid to the diet may be more efficacious in fully reversing the negative effect of lead on growth.