Treatment of patients with unresectable recurrent oral cancer is quite difficult. In particular,there is no scientific evidence to select anti-cancer drugs for patients who were given previous radiation therapy. To select optional chemotherapy regimens, we have employed a new chemosensitivity testing method, a collagen gel droplet embedded culture sensitivity test (CD-DST) for patients with unresectable oral cancer. Six oral cancer patients with recurrence and/or metastatic disease were treated with the optional chemotherapy based on the results of CD-DST. No result was obtained due to a problem of poor growth of tumor cells in one case. In another case, we could not find a sensitive anti-cancer drug among the agents we examined. These 2 patients were treated with selected palliative pain control therapy. Optional chemotherapy based on the results of CD-DST was given to 4 patients showing sensitivity to the anti-cancer drugs examined. Tumor recession or tumor dormancy was observed clinically during a definite period. Toxicity was mild and the median survival was 10.9 months. We therefore conclude that the examination with CD-DST may provide important scientific evidence to determine a suitable chemotherapy for patients with advanced oral cancer.