In　this　paper　several　kinds　of　high　temperature　molten　salts　were　investigated　experimentally　on　viscosity-temperature　characteristics　with　high-temperature　viscometer.　The　viscosities　of　the　molten　salts　were　measured　and　compared　with　those　from　references　to　verify　the　reliability　of　the　viscometer　and　measuring　methods,　and　a　good　agreement　was　observed　from　the　comparisons.　Then,　two　new　high-temperature　molten　salts　were　made　from　the　HITEC　salt　by　some　additives　and　the　viscosity-temperature　profiles　of　them　were　obtained　by　experiments.　The　results　show　that　the　new　molten　salts　have　much　lower　viscosities,　thus　suitable　for　reducing　the　flow　resistance　in　transportation　system　of　high-temperature　solar　thermal　power　generation.