Abstract: Objective：To investigate the radiosensitizing effect of 5-Nitroindazole-3-formyl Glycine on animal model. Methods：Kunming mice transplanted with H22 hepatoma were divided into 4 groups randomly, 5-Nitroindazole-3-formyl Glycine alone(divided into 3 sub-group), radiation alone, radiation combinated with 5-Nitroindazole-3-formyl Glycine(divided into 3 sub-group)，each group including 8 mice.The blood flow in the tumor bearing leg of every mouse was interrupted for 10 min for hypoxia. Method of tumor growth delay was used in the experiment. Results：Sensitizing enhancer ratio on the 3 groups was 1.75、2.0、1.25 respectively. Conclusion：3 dosages of 5-Nitroindazole-3-formyl Glycine all have radiation-sensitizing effection on H22 hepatoma and are avirulent to mice．