We examined the fecal fat excretion of mildly hypertriacylglycerolemic subjects who ingested soft cookies containing 1(3)-behenoyl-2,3(1)-dioleoyl-rac-glycerol (BOO) for 7 days. The subjects included 14 healthy men (average age; 44.9 ± 1.7) whose fasting plasma triacylglycerol level ranged from 150 to 250 mg/dL. Every day for 7 days, the subjects ate 5 soft cookies containing margarine with the BOO-rich experimental oil (BOO intake, 2.46 g/day). The placebo group ate soft cookies containing margarine without BOO. This study was a randomized double-blind, placebo-controlled, crossover study. Feces were collected for 3 days prior to the end of the treatment period, and fecal fat and fatty acid composition were determined. The fecal wet weight was significantly increased in BOO group compared with that in the placebo group. Moreover, fecal fat and fatty acid level were significantly higher in the BOO group than in the placebo group. There were no significant differences in the fecal fatty acid composition of the BOO and placebo groups. These results suggest that dietary BOO increases fecal excretion of dietary fat in humans. However, BOO does not increase the excretion of specific fatty acids; it increases the excretion of all fatty acids of dietary origin, which may lead to lower and delay intestinal absorption of dietary fat.