This study was done on fifty patients, with ages ranging from two months to three years suffering from acute infectious diarrhea evidenced by stool culture. Twenty-five patients received Lactobacillus therapy and twenty-five patients served as a control group. The duration and frequency of diarrhea in both groups were recorded, and stool culture was repeated after termination of diarrhea and the results were compared. A significant relation was found between therapy with Lactobacillus and shortening of the duration and frequency of diarrhea.