Sixty-five Japanese patients with primary carcinoma of the gallbladder treated in the Department of Surgery I at Kyushu University from 1965 through 1982 were reviewed. Forty-one patients had histologically proven primary carcinoma and the other 24 patients were diagnosed by laparotomy and/or combination of several diagnostic procedures. The female to male ratio was 1.5 to 1. The peak incidence was at the ages of 60-69 years for both sexes. Gallstones were found in 53 per cent of resected patients and were demonstrated in 58 per cent of unresected patients by ultrasonography. Laparotomy was performed on 50 patients and the tumor could be removed in 15 patients. Resection could be done in only one of 18 patients correctly diagnosed. Fourteen of 15 patients who underwent resection had been diagnosed as cases of benign lesions. Curative resections were feasible in six of 15 patients. In curative resection cases, the longest survival time was 42 months; and in cases of non-curative resection, 26 months. Most of the nonresected patients died within 6 months with an operative mortality of 16.6 per cent. This report reinforces the difficulty in diagnosis and the poor prognosis for patients with primary carcinoma of the gallbladder. However, ultrasonography seems to be the best tool at present for detecting early cancer, especially cancer of the polypoid type. We hold the view that more radical approaches for relatively early cancer will enhance the operative results.