Research results on corrosion behavior of Flibe (LiF-BeF2 molten salt) against structural materials are reviewed. Thermodynamic calculation and static experiment were carried out. It was found that some kinds of oxide films may work as a protective scale for ferritic steel. For V-based alloy, on the other hand, no stable oxide film can exist in the presence of Flibe. It was also found that Redox control might protect V-based alloy against corrosion.