High efficiency solid-state neutron moderator materials are crucial component in micro-nuclear reactor. The main function of neutron moderator is to reduce the energy of neutrons produced by fission to a range that sustains further fission. Meanwhile, moderator materials are also one of the core structural materials in reactors. The application of high-temperature-resistant and efficient neutron moderator can help promote the development of miniaturization and mobility of micro nuclear reactors. Starting from the principle of moderators, several promising high-temperature resistant and efficient neutron moderators were summarized. The development prospects for different moderators were discussed, providing valuable guidance for subsequent researches and applications.