This study investigated the effects of xylooligosaccharide on feces bifidobacteria proliferation, lactic acid concentration and lipid metabolism in healthy woman. Fourteen volunteers were randomly assigned to 2 groups : 1.4 g/day xylooligosaccharide intake group, 2.8 g/day xylooligosaccharide intake group. The duration of the study was 28 days. The amount of feces and excretion time were not affected by xylooligosaccharide intake. The color of feces changed to yellow brown, and hardness of stool and effort to evacuation were reduced by xylooligosaccharide intake. Xylooligosaccharide intake reduced the fecal pH significantly after 14 days in 2.8 g/day intake group (p < 0.05). The number of fecal bifidobacteria were significantly increased after 28 days in 1.4 g/day intake group (p < 0.05), and in 2.8 g/day intake group, the number of fecal bifidobacteria significantly increased after 14 days (p < 0.05). Water contents of feces were not affected by xyloolgosacchride intake. The fecal triglyceride and cholesterol concentrations were increased in 2.8 g/day intake group (p < 0.05), and in 1.4 g/day intake group, fecal cholesterol concentration only was increased (p < 0.05). The fecal lactic acid concentration was significantly increased in 2.8 g/day intake group (p < 0.05). Serum trigly-ceride, cholesterol and glucose concentration were significantly decreased in 2.8 g/day intake group (p < 0.05). In conclusion, xylooligosaccharide dietary supplementation may be beneficial to gastrointestinal health and lipid metabolism, and 2.8 g/day intake was more effective than 1.4 g/day intake.