Chemosensitivity of salivary gland and oral cancer cell lines to 14 antitumor drugs was tested using a tetrazolium-based colorimetric assay and the relative antitumor activity (RAA) of the drugs was compared. Adriamycin (ADM), methotrexate and fluorouracil (5-FU) showed the most potent RAA against the cell lines while cantharidin did not. The rank orders of other 10 drugs against each cell line differed from each other.