In cases of early gastric cancer (EGC), the depth of tumor invasion and histologic type are important factors in its prognosis. To predict the depth of invasion and histologic type by a double-contrast barium study of the stomach, 304 consecutive patients with EGC were analyzed, comparing barium study with pathologic findings. We predicted the depth of invasion and histologic type according to the lesion size, surface pattern, and surrounding mucosal pattern. The depth of tumor invasion was correctly diagnosed in 65.3% (66 of 101) of cancers limited to the mucosal layer (m), and in 59.1% (110 of 186) of cancers which have invaded to the submucosal layer (sm). The histologic type was correctly predicted in 78.9% (56 of 71) of a differentiated adenocarcinoma, and 73.1% (57 of 78) of an undifferentiated adenocarcinoma. Prediction of the depth of tumor invasion and histologic type was promising and showed good correlation to the pathologic findings.