OBJECTIVE:　To　study　the　radiosensitizing　effect　of　resveratrol　on　human　hypo　pharyngeal　squamous　cell　carcinoma　(FaDu)　cells　in　nude　mice.METHODS:　Forty-three　nude　mice　bearing　FaDu　cell　xenografts　were　randomized　into　control　group,　radiotherapy　(12　Gy)　group,　resveratrol　treatment　(50　mg/kg)　group,　and　radiotherapy　plus　resveratrol　treatment　group.　After　corresponding　treatments,　the　tumor　volume　in　the　mice　was　measured　every　3　days,　and　the　microvessel　density　(MVD)　in　the　tumor　was　evaluated　with　CD31　immunofluorescence　histochemical　staining.RESULTS:　The　tumor　volume　and　weight　were　the　smallest　in　mice　receiving　radiotherapy　plus　resveratrol　treatment　(P＜0.05)　but　comparable　between　those　having　resveratrol　treatment　alone　and　the　control　mice.　Radiotherapy　plus　resveratrol　treatment　resulted　in　a　tumor　inhibition　rate　of　76.64%　and　a　significantly　decreased　MVD　in　the　tumor　compared　with　the　other　3　groups.CONCLUSION:　Resveratrol　can　produce　a　radiosensitizing　effect　on　human　hypopharyngeal　carcinoma　in　nude　mice.