The objective of the present study is to know the effect of lead nitrate on enzymatic and non-enzymatic antioxidant activities in selected tissues of the fish Labeo rohita fingerlings (10 ± 2g). The fish were exposed to a sub-lethal concentration of 1.56mg L^-1 (1/25^th of 96 hrs Lc₅₀ value of lead nitrate) for a period of 60 days. At end of experimental period, superoxide dismutase (SOD), catalase (CAT) and reduced glutathione (GSH) in gill, liver, muscle and kidney tissues were assayed. The levels of oxidative stress biomarkers were found to be decreased significantly (p<0.01 and p<0.05) in gill, liver, muscle and kidney of the test fish. The changes in these parameters were intensified as period of exposure increases.