Abstract: Objective To evaluate the therapeutic efficacy of transcatheter arterial chemoembolization (TACE) for advanced oral carcinoma by observing the pathological changes of the carcinoma tissues after the interventional therapy. Methods Twenty cases of advanced oral carcinoma involving the tongue (16 cases), gingiva (2 cases) and the floor of the mouth (2 cases) were enrolled in this study. Intubation with Seldinger’s technique from the femoral artery to the external carotid artery was performed in all the cases. With the assistance of digital subtracting angiography (DSA), cisplatin, adriacin and mitomycin C were injected through the branches of the external carotid artery into the involved tissues with embolization using gelatin sponge. Surgical resection of the tumor was performed 1 to 4 weeks after TACE, and the specimens were observed under light microscope and transmission electron microscope. Results Significant changes occurred in the carcinoma tissues, manifested by reduced carcinoma cells, karyopyknosis, vacuolar degeneration and focal coagulation necrosis. The disintegrated carcinoma nests were encapsulated and underwent organization by hyperplastic fibrous connective tissues with inflammatory cell infiltration. The connective structures between the carcinoma cells disappeared and resulted in broadened intercellular space. Conclusion Preoperative administration of arterial chemoembolization may cause degeneration and necrosis of oral carcinoma, which can be helpful to distinguish intraoperatively the carcinoma from normal tissues; as for the inoperable cases, TACE may inhibit the tumor growth and prolong the survival of the patients.