The development of nuclear technology is closely and inseparably related to the improvements of materials irradiation performance.The irradiation damage of nuclear materials is an important issue of characteristics and difficulties.Because of the excellent features,SiC becomes one of the candidate materials for the cladding material and structure material in fast neutron reactor and fusion reactor.As one of the polytypes,4H-SiC has prospective important applications in a strong irradiation environment.In this work,molecular dynamics(MD)simulation was performed to study the irradiation-induced cascade damage in single-crystalline 4H-SiC to get the microscopic evolution during the irradiation,in the aim of getting access to the detail that we cannot get from experiments.The software LAMMPS was used to simulate the damage formation process and the recovery process.The results showed that the initial project direction,the temperature and PKA energy exerted significant effects on the number and morphology of defects.