Objective: Based on the new diagnostic criteria for osteoradionecrosis of jaws (ORNJ), to establish an animal model with controllable bone defect range and early and mild ORNJ characteristics. Method: The method of single high-dose irradiation using an electron linear accelerator was applied. According to the irradiation dose, the animals were divided into group a as control group, group b as 12Gy group, and group c as 14Gy group. Six New Zealand white rabbits were randomly assigned to each group. Group b and group c were uniformly selected for further radiotherapy in the right mandibular area. After one week, all animals were prepared with a standard bone defect with a diameter of 5mm and a depth of 1mm at the right mandibular angle. Execute after 4 weeks and conduct a general observation; Comparison of CBCT scan and HU values of mandibular specimens; H-E staining histological observation; Observation of Trap staining histology and comparison of osteoclast counts. The experimental results were statistically analyzed using SPSS23.0 software. Result: Four weeks after the bone defect was created, the soft tissue in the surgical area of group b and group c showed mild swelling, the skin turned purple, and erosion and ulceration of the oral mucosa were observed, with group c showing more significant changes; CBCT examination showed that the cortical bone of the irradiated areas in groups b and c was rough, while the cortical bone of group c had poor continuity. No significant changes were observed in the extent of bone defects in each group. The comparison of HU values suggests that groups b and c have significantly decreased compared to group a; H-E staining histological observation suggests that the bone continuity of groups b and c has deteriorated, with a large amount of fibrous tissue proliferation, an increase in blank bone pits without cells, and infiltration of inflammatory cells; Trap staining revealed a significant increase in osteoclasts in group c compared to group a. Conclusion: By using an electron linear accelerator and selecting New Zealand white rabbits, a single 14 Gy irradiation was applied to the mandibular angle area to create bone defects with consistent specifications. After 4 weeks, an animal model that meets the early diagnostic criteria of ORNJ and has controllable consistency in the range and degree of bone defects can be established.