In　order　to　get　the　natural　convection　heat　transfer　mechanism　of　molten　salt,　the　experimental　investigation　of　natural　convective　heat　transfer　of　LiNO3　was　studied　after　it　was　simulated　by　numerical　calculation.　Experiment　was　carried　out　on　the　natural　convection　heat　transfer　of　air　and　water　around　the　fine　wire　using　the　method　of　Joule　heating.　The　results　showed　that　the　natural　convection　heat　transfer　of　air　and　water　around　the　fine　wire　agreed　well　with　Fand＇s　correlation.　Based　on　the　aforementioned　experiment,　the　natural　convection　heat　transfer　of　molten　salt　LiNO3　was　studied　by　experiment　and　the　same　results　were　got.　Therefore,　the　natural　convection　heat　transfer　of　molten　salt　can　be　calculated　by　Fand＇s　correlation,　which　takes　into　consideration　the　effect　of　viscosity　dissipation.