In　order　to　obtain　the　natural　convection　heat　transfer　mechanism　of　molten　salt,　an　experimental　research　of　natural　convection　heat　transfer　around　a　horizontal　fine　copper　wire　was　carried　out　by　Joule　heating　method.　Firstly,　the　experimental　method　was　verified　using　water　and　ethanol　as　heat　transfer　media.　Then,　the　natural　convection　heat　transfer　of　molten　salt　around　the　fine　wire　was　studied.　The　experimental　results　showed　that　the　Nu　number　of　natural　convective　heat　transfer　of　molten　salt　turned　toward　to　the　predicted　value　of　Morgan　correlation　with　the　rise　of　molten　salt　temperature.　Therefore,　it　is　needed　to　further　study　the　natural　convective　heat　transfer　of　molten　salt　by　considering　the　property　of　molten　salt.