Molten　salt　as　phase　change　materials　can　be　used　as　thermal　storage　medium　in　concentrating　solar　power　(CSP)　system.　It　is　possible　to　significantly　improve　the　thermal　properties　of　molten　salt　by　adding　nanoparticles　to　molten　salt.　Nanofluids　were　synthesized　by　dispersing　20　nm　SiO2　particles　to　potassium　nitrate,　sodium　nitrate,　and　solar　salt　(60%　NaNO3　and　40%　KNO3,　mass　fraction)　respectively.　Nanofluids　were　prepared　by　water-solution,　sonication,　and　evaporation.　The　thermo-physical　properties　(latent　heat,　specific　heat　and　molting　point)　of　nonofluidswere　characterized　by　DSC　method,　and　the　thermal　diffusivity　was　analyzed　by　laser　flash　apparatus　(LFA).　Results　show　that　mass　fraction　of　20　nm　SiO2　particles　significantly　enhanced　latent　heat,　specific　heat　and　thermal　conductivities　of　potassium　nitrate,　sodium　nitrate,　and　solar　salt.　Compared　with　base　salt,　the　average　specific　heat　improved　of　solar　salt,　potassium　nitrate,　sodium　nitrate　with　20　nm　SiO2　nanoparticles　was　found　to　be　4.7%-15.89%,　3.9%-33.5%,　1.9%-11.86%　in　liquid,　and　the　maximum　thermal　conductivity　increasedby　a　maximum　of　17.16%,　39.7%,　and　9.5%,　respectively.　©　All　Right　Reserved.