In　this　paper,　the　experimental　study　on　the　forced　convection　heat　transfer　between　molten　salt　and　heat　transfer　oil　was　carried　out　by　using　the　binary　mixed　molten　salt　(KNO3-Ca(NO3)2)　prepared　by　our　group.　The　total　heat　transfer　coefficient　of　the　molten　salt-heat　transfer　oil　under　different　working　conditions　was　obtained.　The　convective　heat　transfer　coefficient　and　the　convection　criterion　number　correlation　of　the　molten　salt　in　the　tube　and　the　molten　salt　side　under　the　fully　developed　turbulent　flow　and　transitional　flow　in　the　tube　were　obtained　respectively　by　the　Wilson＇s　Separation　Method　and　the　Least　Squares　Method.　The　results　show　that　the　maximum　deviation　of　turbulent　experimental　data　is　+23%　compared　with　the　classical　correlation.　By　considering　the　variable　properties　of　high-temperature　molten　salt,　the　viscosity　equation　is　used　to　correct　the　Dittus-Boelter　equation　correlation.　It　is　found　that　the　maximum　deviation　between　the　modified　Dittus-Boelter　equation　and　the　experimental　test　results　is　-15%.　The　deviation　value　is　significantly　reduced.　The　maximum　deviation　of　the　transitional　flow　experimental　data　from　the　Hausen　equation　and　the　Gnielinski　equation　is　10%.　The　test　shows　that　the　experimental　results　of　this　work　are　in　good　agreement　with　the　classical　heat　transfer　formula　mentioned　above,　which　isdications　that　the　heat　transfer　relationship　is　still　applicable　to　high　temperature　molten　salt.　©　2021,　Solar　Energy　Periodical　Office　Co.,　Ltd.　All　right　reserved.