Effects of lycopene supplements on antioxidant capacity were studied in Crucian Carp, Carassius auratus, with average length 22.4±1.13 cm and weight 180.60 ± 37.23 g. Fish were fed a commercial diet supplemented with Lycopene at levels of 0.50%, 0.75%, 1.00%, and with 1.5% fish oil as the control in cages for 50 days. That is, four diets contained Lycopene at 0, 75, 112.5, and 150 mg·kg^-1 for a control diet and other three diets containing Lycopene. Twenty fish was randomly taken from each cage. As biomarkers, T-SOD, MDA, GSH-Px, NO, and ·OH were measured in blood serum. The experimental data were presented in mean ± standard deviation (SD). Duncan test was performed for the multiple comparisons among four diets using SPSS 11.5 version. The study shows: The levels of T-SOD in fish blood serum were 8.49, 43.33, and 48.57 U·mL^-1 higher in fish fed with three diets added lycopene than that of the control. The levels of T-SOD were significantly higher (P<0.05) in fish fed with diet added 112.5 and 150.0 mg·kg^-1 lycopene than that of the control. The levels of MDA in the blood serum of fish fed with diets were 3.75, 4.55, and 2.70 nmol·mL^-1 lower than that of control. But, no significant difference was found in levels of MDA in fish fed diets added 75.0, 112.5, 150.0 mg·kg^-1 lycopene oil and the control. The levels of GSH-Px activity in the blood serum of fish fed with three lycopene diets were 99.32, 138.77,122.61 U higher compared to the control. The GSH-Px activity in blood serum of fish fed diets added lycopene was significantly higher (P<0.05) than that of the control. The levels of NO in fish fed diets adding lycopene were 12.83, 8.30, and 13.02 μmol·mL^-1 higher than that of control. The levels of NO in fish fed 75 and 150 mg·kg^-1 lycopene were significantly different (P<0.05) than that of control fish. The activities of ·OH in fish fed lycopene were 318.50, 290.91, and 277.99 U·mL^-1 lower than that of control. The activity of ·OH was significantly decreased (P<0.05) in fish fed diet added 75.0 mg·kg^-1 lycopene than that of the control. No significant differences were found in levels of T-SOD, GSH-Px, MDA, NO, and ·OH in blood serum of fish fed diets added with 75.0, 112.5, 150.0 mg·kg^-1 lycopene. The experiment demonstrated that lycopene as an antioxidant added to a commercial diet can significantly improve the antioxidant capacity of Crucian Carp.