We have performed endoscopic ultrasonography (E.U.S.) to diagnose the esophageal carcinoma especially about its mural invasion and its lymph nodes involvement. The ultrasonography for the resected specimens in the water tub delineated the esophageal wall as five or seven layers. In the clinical E.U.S., the normal esophageal wall was delineated as three or five layers and the thick hypoechoic layer corresponded to the proper muscular layer. The superficial type of esophageal cancer was demonstrated as the thickness of the wall, and the diagnosis for the depth of invasion was possible. The advanced cancers were clearly demonstrable and the diagnosis for the direct invasion to the adjacent organs were also possible. The overall accuracy of the diagnosis for the depth of invasion was 70%. The lymph nodes were seen clearly and the overall accuracy of the lymph node metastasis showed 88%.