ABSTRACT: Objective: The objective of this study was to assess the effect of a new prebiotic (Novel Bifidogenic Growth Stimulator (BGS)) on improving bowel movement of Thai women with non-specific, mild constipation. Materials and methods: A one group clinical trial was carried out in 74 subjects with non-specific and mild constipation. The six-week study included three two-week periods: pre-intake period, intake period, and post-intake period. Subjects were asked to take one sachet (1.5g) of BGS powder per day for two weeks from Day 15 to Day 29 (intake period). The record of study product use was included on a Daily Compliance Form. Results: After taking powdered BGS, the subjects significantly increased frequency of defecation, had reduced difficulty on defecation with increased quantity and improved characteristics of stool, in shape, color, and odor. During the post-intake period, these effects waned a bit, but were still improved from the pre- intake period. Conclusion: After two weeks of taking BGS powder, the subjects showed improvement in bowel movement with satisfaction of results.