Abstract: With the theory of anti-angiogenesis therapy for malignant tumors， recombinant human endostatin（Endostar）as a promising novel medicine to treat malignant tumors，represents synergistic antitumor effects in combination with conventional radiotherapy. Its radiosensitization effect has been demonstrated by a variety of laboratory and clinical experiments，and the underlying mechanisms may include normalizing tumor vasculature，alleviating inner hypoxia，inhibiting endothelial cell proliferation and migration，inducing endothelial cell apoptosis，cell cycle changes，and angiogenic factors regulation. Endostar in combination with radiotherapy may become a new and effective treatment strategy of anti-cancer.