Detoxication effect of red ginseng on physio-function of goldfish treated with endosulfan was investigated by means of biochemical analysis and agarose gel electrophoresis. After treatment of endosulfan, the total LDH activity in gill was slightly decreased and that in serum was increased about twice as compared with the control group. In the gill, enzyme activity of LDH_1 fraction was increased and that of LDH_5 was decreased by treatment of endosulfan. In the serum, the total LDH activity of endosulfan-red ginseng group was increased in comparison with those of control and endosulfan groups. The levels of total LDH activities and electrophoretic patterns of LDH isozymes of endosulfanred ginseng group were similar to those of the control group in gill.