Objective   To observe the ultrastructure of Barrett’s esophageal epithelium by transmission electron microscopy and to investigate the related clinical significance.   Methods   Barrett’s esophagus was screened by endoscopy. Biopsy specimens in the distal oesophagus were fixed in 10% buffered formalin for the histopathological diagnosis. Some biopsy specimens from the patients with Barrett’s esophagus showing specialized intestinal epithelium were fixed in 2.5% glutaraldehyde for subsequent study by transmission electron microscopy.   Results   Transmission electron microscopy found an intermediate cell type between the mucous cell and the goblet cell in the surface of Barrett’s specialized intestinal metaplasia and a special cell type with both squamous and columnar cell features under the surface of Barrett’s specialized intestinal metaplasia.   Conclusion   The special cell type of both squamous and columnar cell features found by transmission electron microscopy may be the result of transformation of multipotential stem cells of squamous epithelial origin. The intermediate cells may represent an intermediate stage in the development of Barrett’s specialized intestinal metaplasia.