He specializes in liver, gastrointestinal, and pancreatic pathology. His research interests are in liver tumors, nonalcoholic fatty liver disease, liver transplantation and viral hepatitis. He has authored over 200 peer-reviewed manuscripts and many review articles and book chapters in these fields. Dr. Yeh is also the author of the AFIP Liver Tumor Fascicle, 4th series. Recently he is particularly interested in the investigation of fatty liver contributing to liver tumors, as well as vascular diseases in liver.