Abstract: The thermal insulation layer of a liquefied natural gas (LNG) storage tank is a critical component for ensuring its insulation and aseismic performance. At present, the research of thermal insulation layer mainly focuses on the traditional material expanded perlite. The use of other materials for insulation has not been attempted. New materials, rock wool plate and polyurethane plate are presented as insulation layer for heat transfer and seismic analysis of large LNG storage tanks based on fluid-structure interaction. The thermal insulation and aseismic performance of expanded perlite, rock wool plate and polyurethane plate in tanks are evaluated by numerical simulation under various liquid fill levels and seismic waves. The study results show that: compared with expanded perlite and rock wool plate, polyurethane plate can significantly reduce the acceleration, hydrodynamic pressure and strain of the tank under seismic waves. The storage tank using the new insulation material, polyurethane plate, demonstrates superior aseismic performance. At the same time, the polyurethane plate can remarkably enhance the thermal insulation capacity of the storage tank and isolate the heat transfer. In addition, the particulate expanded perlite can easily cause stress concentration in the tank wall under seismic conditions, while the layered polyurethane plate can effectively solve such stress concentration problem. Therefore, it is recommended to preferentially use polyurethane plates as insulation materials to improve the overall safety of storage tanks.