Abstract: The influence of four immune opotentiators on immune cells and antioxidant enzymes activity of red and white tube-feet sea urchin groups, Strongylocentrotus intermedius, were studied in this paper. The results showed: 1) The pigment cells number in the tube-feet of two sea urchin groups showed a variation trend from descending to increasing after dealing with lipopolysaccharide, but the change was not significant (P>0.05). The pigment cells number of red tube-feet individuals was significantly higher than that of white tube-feet individuals. The phagocytic cells in coelomic liquid of two groups both increased after treating with lipopolysaccharide, but the red tube-feet groups were not changed significantly (P>0.05). The phagocytic cells number of red tube-feet individuals was significantly higher than the white tube-feet individuals. The pigment cells in coelomic liquid were both increased after treatment with lipopolysaccharide. After dealing with the Ganoderma lucidum polysaccharides, the pigment cells were decreased slightly in the red individuals. The phagocytic cells in coelomic liquid were decreased in the white individuals, but it showed a rising trend before decreased in the red individuals. The number of phagocytic cells in the white individuals was higher than red individuals. The pigment cells in coelomic liquid were both decreased after rising in two groups. 2) We also studied the difference on antioxidant enzymes in coelomic liquid between the two groups after treatment with four immune opotentiators (ganoderma lucidum polysaccharide, glucan, lipopolysaccharide, and double-stranded RNA). The result showed that the enzyme activities were all increased after dealing with four immunopotentiators and the red tube-feet group increased more evidently. This result suggested that both Ganoderma lucidum polysaccharides and lipopolysaccharide could increase immune cells number, but no obvious effect on tube cells. The four immunopotentiators could all increase T-AOC, CAT and SOD activities.