The conduction-cooled HTS SMES is operated in cryogenic and high vacuum condition. Thus. Insulation design at cryogenic temperature and high vacuum is a key and an important element that should be established to accomplish compact design is a big advantage of HTS SMES. However, the behaviors of insulators for cryogenic conditions in vacuum are virtually unknown. Therefore, active research and development of insulation concerning application of the conduction cooled HTS SMES was needed. In this study, the insulation characteristics at experimented high vacuum and cryogenic similar to running condition of SMES system. Also, investigated about insulation characteristics of suitable some materials to insulator for conduction-cooled HTS SMES. As these results. the basis data was obtained for insulation materials selection and insulation design for development of 600kJ class conduction-cooled HTS SMES.