Effects of Dasom Valley and Bora Valley on fecal microflora, fecal moisture, and fecal pH of twelve healthy human volunteers were investigated. Numbers of Bifidobacterium, Clostridium perfringens, Escherichia coli, and Lactobacillus of control group were $9.24{pm}0.63$, $4.44{pm}1.21$, $7.75{pm}0.38$, and $6.98{pm}0.81$ (Log CFU/g wet feces), respectively. During administration of Dasom Valley, numbers of Bifidobacterium and Lactobacillus were $10.70{pm}0.44$ and $8.84{pm}0.77$, whereas those of C. perfringens and E. coli were $2.96{pm}1.50$ and $6.69{pm}0.29$, respectively. Administration of Dasom Valley significantly increased growth responses of beneficial bacteria, Bifidobacterium and Lactobacillus, whereas those of harmful bacteria, C. perfringens and E. coli, significantly decreased. Moisture content of feces increased and fecal pH decreased with intake of Dasom Valley. Intake of Bora Valley slightly increased numbers of Bifidbacterium and Lactobacillus and slightly decreased those of C. perfringens and E. coli. Results indicate Dasom Valley has greater intestinal-modulating effect than Bora Valley and Atlantic. Daily intake of Dasom Valley may normalize disturbed physiological functions, resulting in improvement of growth and composition of microbial community within intestinal tract.