In　order　to　obtain　the　laminar　natural　convection　heat　transfer　mechanism　of　molten　salt,　the　natural　convection　heat　transfer　of　multi-component　molten　salts　around　a　cylinder　with　different　diameters　was　studied　by　simulation.　The　result　showed　that　the　natural　convective　heat　transfer　of　molten　salt　in　the　Rayleigh　number　range　of　1.57x10(-2)-2.03x10(6)　cound　be　predicted　by　Fand＇s　correlation　that　took　the　viscous　dissipation　into　consideration,　in　addition　to　Prandtl　and　Rayleigh　numbers.　With　the　increasing　in　Rayleigh　number,　the　effect　of　viscous　dissipation　decreased,　so　the　other　correlations　that　neglected　the　effect　of　viscous　dissipation　cound　also　predict　the　natural　convection　of　molten　salt　well.　Those　results　cound　be　a　foundation　for　predicting　the　natural　convection　heat　transfer　of　molten　salt.　(C)　2015　The　Authors.　Published　by　Elsevier　Ltd.