OBJECTIVE: To identify interstitial cells of Cajal (ICC) in the common bile duct of Kunming mice. STUDY DESIGN: Common bile ducts obtained from the Kunming mice were prepared for immunohistochemical investigations using the c-kit antibody. Immunoelectron microscopy was used to detect the expression of c-kit in the ICC of the common bile duct. Transmission electron microscopy showed ultrastructure of ICC in the murine bile duct. Reverse transcription–polymerase chain reaction (RT-PCR) and western blot were used to confirm the expression of mRNA specific for the c-kit gene and production of c-kit protein in the Kunming mice common bile duct. RESULTS: Immunohistochemistry revealed that ICC in the murine common bile duct are c-kit positive and the ICC are located in the tela submucosa and the tunica muscularis of the murine common bile duct and do not connect with each other. Immunoelectron microscopy confirmed the expression of Kit by ICC in the murine common bile duct. Transmission electron microscopy showed that ICC in the murine common bile duct have long processes, abundant mitochondria, plenty of smooth endoplasmic reticulum (sER), a lot of lysosomes, and dense bodies. The caveolae of ICC are distinctive. At the same time, RT-PCR indicated that the Kunming mice common bile duct expressed mRNA specific for the c-kit gene, and western blot analysis showed the evidence of production of c-kit protein in the Kunming mice common bile duct. CONCLUSION: ICC are found in the Kunming mice common bile duct, which is likely to lead to the development of motility study of the common bile duct. © Science Printers and Publishers, Inc.