Of 3000 autopsy cases, consisting primarily of older patients, asymptomatic gallbladder carcinomas were found in 15 (0.5%); the incidence among all gallbladder carcinomas (80 cases) was 18.8%. In contrast to symptomatic gallbladder carcinomas, all of which were classified as Stage III (9.3%) or Stage IV (90.7%) disease, 80.0% of asymptomatic cases were classified as Stage 0 (13.3%), I (20.0%), or II (46.7%). Histologically, all the symptomatic cases of gallbladder carcinoma had invasion to the serosal or subserosal layer of the gallbladder as well as to the hepatoduodenal ligament. Lymphatic and hematogenous metastases of the symptomatic carcinomas were found in 94.4% and 64.8%, respectively. On the other hand, the carcinoma in the asymptomatic group was retained in the mucosal layer (M) in four cases, in the muscular layer (MUS) in one case, in the subserosal layer (SS) in nine cases (INF beta in seven cases and INF r in two in the mode of infiltration), and in the serosa (SE) in one case. However, cancerous invasion to the hepatoduodenal ligament or lymphatic metastasis was found in only two cases, whereas hematogenous metastasis was not found in any of them. Cancerous extension beyond the gallbladder wall was apparently rare in the cases of SS invasion, as well as in those of M or MUS invasion. It was suggested that, for radical resection of gallbladder carcinoma, it is very important to find it in an asymptomatic stage.