Objective: To study effects of cisapride on the human gallbladder volume and emptying. Methods: Fasting and postprandial gallbladder volumes were measured with ultrasonography in 15 healthy volunteers before and after taking cisapride orally. Gallbladder volumes were normalized to gallbladder ejection frequency (GBEF). Results: The fasting gallbladder volume in 15 healthy subjects did not change before or after cisapride administration (P>0.05). Postprandial gallbladder volume 30min after taking became smaller than that before taking cisapride (P<0.05). GBEF was significantly enhanced that after cisapride administration(P<0.001). Conclusion: Cisapride had no effect on the fasting gallbladder volumes but significantly promoted postprandial gallbladder contraction and emptying.