Abstract: Objective To investigate the efficacy and safety of chemotherapy combined with rhendostatin（endostar）against stage ⅡB ostosarcoma. Methods Patients of stage ⅡB ostosarcoma enrolled in Beijing Jishuitan Hospital from January 2008 to April 2012 were divided into combined group and control group. The regimen of chemotherapy was as follows： methotrexate 10g／m2 iv d1，ifosfamide 3g／m2 iv d1-d5，cisplatin 120mg／m2 iv d1，doxorubicin 30mg／m2 iv d1-d3. Based on the same chemotherapy，endostar was added in combined group（15mg iv d1-d14，21 days was a cycle，for 4 cycles）. Results A total of 388 patients were enrolled in this study， and 58 cases were excluded in the final analysis. In the 330 patients could be evaluated，272 cases were in control group and 58 in combined group. Patients were followed up 6.59 months with a median period of 20.2 months. In the control group，1-，2- and 3-year distant metastasis-free survival rates were 79％，70％ and 65％ respectively，while those of combined group were 93％，86％ and 77％ with statistical difference（P=0.045）. In control group，1-，2-and 3-years of progression-free survival rates were 76％，66％ and 60％，respectively，while those of combined group were 90％，83％ and 74％ with statistical difference（P=0.025）. In the control group，1-，2-and 3-year overall survival rates were 94％，84％ and 79％，while those of combined group were 98％，94％ and 85％ without statistical difference（P=0.220）. The side effects in the two groups were mainly in grade 1-2, and the common grade 3-4 side effects were leucopenia，anemia，hepatic dysfunction，nausea and vomiting. There was no difference in side effects of the two groups. Conclusion The combination of chemotherapy and endostar can significantly improve the distant metastasisfree survival and progression-free survival in osteosarcoma patients，with tolerable side effects，worthy further study.