Two cases of malignant mixed tumor of the gallbladder are reported. The histology of both revealed malignant mesenchymal elements (chondroid, osteoid, fibrous) admixed with adenocarcinoma. One patients had widespread disease and died three days following diagnosis. The second patient had tumor limited to the gallbladder and is alive with no evidence of disease 31 months following cholecystectomy. Only three other such tumors are reported in the English literature. Analysis of these cases indicates that the behavior and etiology of malignant mixed tumors may be similar to that of carcinomas of the gallbladder.