Objectives : The aim of this study was to evaluate gastrointestinal parasympathetic nerve activation and pyloric valve function in patients with functional dyspepsia through analysis of bowel sounds and to investigate clinical characteristics associated with the parameters of bowel sounds. Method : We surveyed clinical characteristics of patients by using a questionnaire about functional dyspepsia. Bowel sounds were recorded for 15 minutes during fasting state and for 40 minutes during postprandial state. We then classified the patients into 3 groups by abnormal states of bowel sounds, specifically by the percentage of B.S. and dominenet frequency, and studied clinical characteristics in each group. Results : Among the 182 subjects, patients who had low activity of parasympathetic nerve were 25.8% and showed a tendency of female-dominant, family history and more frequent abdominal pain. Those who had pyloric valve disturbance were 24.1% and showed no tendency by sex distribution, family history and complained of indigestion sensation. Patients who had both disorders were 10.9%, and their clinical characteristics were non-specific. Conclusion : Analysis of bowel sounds may be useful in evaluating pathophysiological factors of functional dyspepsia.