This experiment was conducted to evaluate the effects of dietary copper-vitamin C interaction on growth performance, copper accumulation in the liver and immune function of Lateolabrax japonicus. Six isoenergetic and isonitrogenous semi-purified diets were prepared according to a 2×3 interaction design, which included 2 copper levels ［proper (3.5 mg/kg) and high (35 mg/kg)］, and 3 vitamin C levels (50, 500 and 1 000 mg/kg). The experimental groups were S50, S500, S1000, H50, H500 and H1000, which had 3 replicates per group and 30 fish per replicate. The experiment lasted for 6 weeks. The results showed as follows: 1) the final weight and specific growth rate (SGR) of group S500 were significantly higher than those of group S1000 (P<0.05); the condition factors (CF) of groups S500 and H50 were significantly higher than that of groups S50 (P<0.05). 2) The copper accumulations in the liver of high copper level groups were significantly higher than those of proper level groups (P<0.05), and were significantly higher than those of group S1000 under interaction (P<0.05). 3) The complement 3 (C3) content in the liver of high copper level groups was significantly lower than that of proper copper level groups （P<0.10）, and that of group H50 was significantly lower than that of group S50 under interaction （P<0.10）; the liver Na+-K+-ATPase activity of group S500 was the highest, and was significantly higher than that of group H1000 （P<0.10）; the liver alkaline phosphatase (AKP) activity of group S500 was the highest, and was significantly higher than that of group S50 under interaction （P<0.10）; the malonaldehyde （MDA） content of proper copper level groups was significantly higher than that of high copper level groups （P<0.10）. The results indicate that fish with the supplementation of copper at 3.5 mg/kg and vitamin C at 500 mg/kg in diet have the best growth performance and the lower copper accumulation in the liver, the immune function is also improved.［Chinese Journal of Animal Nutrition，2011，23（3）：395-402］