Background:Gastrointestinal dysmotility is frequently seen in patients with chronic obstructive pulmonary disease ( COPD). Simo Decoction is used for promoting gastrointestinal motility in clinical practice. Aims:To study the effect of Simo Decoction on gastrointestinal symptoms and motility in patients with COPD. Methods:Thirty-six patients with stable COPD in Shiyan Renmin Hospital from Sep. 2012 to Jun. 2013 were enrolled and received a 28-day course treatment of Simo Decoction oral solution,19 healthy volunteers were served as controls. All subjects were assessed with gastrointestinal symptom rating scale(GSRS). Electrogastrography was performed and levels of vasoactive intestinal peptide(VIP)and intestinal fatty acid-binding protein( I-FABP)in peripheral blood were measured. Patients with COPD were re-examined for the above-mentioned parameters after treated with Simo Decoction. Results:The baseline GSRS score and serum I-FABP level in COPD patients were significantly increased as compared with controls(P<0. 05),while the baseline serum VIP level,as well as the fasting and postprandial normal gastric slow wave percentage in COPD patients were significantly decreased(P <0. 05). After 28-day course of Simo Decoction treatment,all these parameters in COPD patients were improved as compared with those before treatment(P<0. 05),serum levels of VIP,I-FABP and normal gastric slow wave percentage were similar to those of controls. Conclusions:Simo Decoction can ameliorate the gastrointestinal symptoms and dysmotility in patients with COPD. The regulatory effect of Simo Decoction on gastrointestinal motility might be bidirectional.