Salivary gland tumors were found to be increased more than fivefold among survivors of the atomic bombs who had been exposed to high doses of radiation, compared with nonirradiated controls. Despite a small number of proven cases, (22 in all) this finding was determined to be highly significant for the entire group and for histologically malignant types, but not for benign tumors. This represents a new finding in the search for late sequelae of the atomic bombs. In our study the prevalence of tumors was related to younger age at exposure, but not to the interval between exposure and diagnosis. There was no clear association between amount of A-bomb radiation and cell type. The present findings are compared with other reports concerned with radiation and salivary gland neoplasia.