The effects of food restriction on the fecal microflora, moisture, pH, indole, ${eta}$-glucosidas, and ${eta}$-glucuronidase in rate were studied for 4 weeks. Four groups of rats for feeding was allocated to the following experimental trials : (1) control containing 1% cellulose, (2) control with food restriction, (3) treatment of diet containing butterbur, (4) treatment of butterbur combined with diet restriction. Treatment of butterbur combined food restriction significantly (p<0.05) reduced the growth of Bacteroides, Peptococus, Streptococcus, Staphylococcus, and Escherchia coli, respectively. No remarkable changes in the ${eta}$-glucosidase and ${eta}$-glucuronidase activities were observed but indole content significanlty decreased. Based on these results, treatment of butterbur combined with diet restriction in rats had a significantly effect for preventing the growth of those pathogenic microorganims.