Chronic nonspecific diarrhea in children, or toddler's diarrhea, is a frequently encountered entity in pediatric clinical practice. This disorder remains poorly understood. Suggested etiologies include malabsorption, dietary intake and motility abnormalities. We investigated the use of sacrosidase (a yeast sucrase supplement) in children with toddler's diar- rhea. The study outcome was clinical response to sacrosidase supplementation. Children, 1-6 years of age, with toddler's diarrhea were enrolled in an open prospective trial. Stooling patterns were obtained at baseline and while on supplementa- tion. Twelve patients were enrolled out of 40 patients who presented with chronic diarrhea. Eight patients did not respond to standard diet changes and were entered into the trial. With supplementation, 4 out of the 8 patients responded clinically with a decrease in mean daily stool frequency and an improvement in the mean daily stool consistency. Sacrosidase sup- plementation demonstrated a potential benefit in a subset of children with toddler's diarrhea. Response to sacrosidase may suggest excessive sucrose intake or unrecognized partial or complete sucrase deficiency in some children with toddler's diarrhea.