Abstract: Objective: To observe the distribution of interstitial cells of Cajal(ICCs) in Hirschsprung disease(HD),and investigate the role of ICCs in HD.Methods: The distribution of ICCs was examined in 32 patients with HD and 10 normal controls by PV immunohistochemistry.Results: In bowels from normal controls and ganglionic segment from HD,the moderate to large amount of ICCs were observed around the myenteric plexus and at the circular muscle layer.ICCs in these domain appeared as a network structure.On the contrary,the number of ICCs was significantly decreased or even disappeared in between the muscle layers of the ganglionic segment in HD.Conclusions: Abnormal distribution of ICCs in the bowel affected by HD may explain the bowel dysmotility seen in these patients.