Abstract: The micro gas-cooled reactor is one kind of advanced movable micro nuclear power devices with very high inherent safety, which adopts a new type of dispersed multi-coated particle fuel mainly made of silicon carbide (SiC) in fuel system. As a fuel clad material, SiC plays an important role in transferring heat from fuel to coolant, restrains most of the radioactive fission products within its volume. During the lifetime of reactor, the fuel suffers from neutron irradiation, resulting in a series of radiation damage such as displacement damage, irradiation swelling and transmutation, which leads to permanent changes in microstructure and further affects the performance of the whole fuel system. In order to study the neutron-induced radiation damage of SiC-based material in the reactor core, a core model was established using Monte Carlo program, and the displacement per atom (DPA) of SiC material at typical positions in the core was calculated using SPECTRA-PKA code. The processing code SPECTRA-PKA produces all kinds of primary atomic recoil events for SiC material composition exposed to irradiation spectrum. The calculated result shows that the Si primary knock-on atom (PKA) contributes more radiation damage than the C PKA, and its contribution at the maximum, minimum and average dose level of neutron flux is 55.2%, 56.8% and 54.6%, respectively. The annual radiation damage of SiC with the maximum neutron irradiation dose in core is lower than 1 dpa. Elastic scattering plays a dominant role due to the high cross sections at low neutron energy. In addition, inelastic scattering also makes a small contribution. The additional recoils due to the subsequent decay of radionuclides produced by transmutation reactions were further considered using a self-developed neutron activation analysis code named NIAC. The result indicates that the transmutation elements are mainly produced by Si atoms. Compared to the armour materials of plasma facing materials in fusion reactor such as tungsten, the transmutation of SiC is insignificant. This is mainly attributed to two factors: first, the dose level of neutron flux in fusion reactor is much higher than that in micro gas-cooled reactor, and the average neutron energy of fusion reactor is much higher than that of fission reactor, which is easier to induce transmutation reaction of materials; second, the high-Z tungsten is more susceptible to transmutation, generating transmutation elements such as rhenium, osmium, tantalum and hafnium, resulting in changes in the chemical composition of the material. After 3 years irradiation, the PKA of transmutation elements in SiC only makes up about 0.01% of the total and contributes about 0.24% of the predicted DPA rate.