Purpose: This study aims to observe the effect of X-rays on infraorbital nerve of rabbits.Methods: New Zealand rabbits were randomly divided into four groups,among which there were a control group without X-ray irradiation operation and three irradiation groups exposure to 10,20,and 30 Gy X-ray irradiation,respectively(n = 6 in each group).All the rabbits were sacrificed three months following X-ray irradiation operation and the infraorbital nerve of rabbits were extracted.The ultrastructure changes of rabbits infraorbital nerve were investigated by using electron microscope.