Thermal　performance　of　molten　salts　can　be　enhanced　by　nanostructured　materials,　which　can　enhance　the　heat　transfer　capacity　of　heat　pipes　and　further　improve　the　global　efficiency　of　Concentrated　Solar　Power　plants.　In　this　work,　a　eutectic　mixture　of　sodium　bromide,　potassium　bromide,　lithium　bromide　and　calcium　bromide　acted　as　the　base　salt,　into　which　nine　SiO2　nanoparticles　in　three　diameters　were　dispersed　to　form　twenty-two　nano-bromides　in　total.　The　thermodynamic　properties　of　the　base　salt　and　nano-bromides,　e.g.　the　thermal　stability　and　the　phase　change　performance　were　investigated　experimentally　and　analytically.　It　was　observed　that　the　size　and　the　mass　concentration　of　the　SiO2　nanoparticles　exhibited　significant　influence　on　the　heat　of　fusion　and　the　decomposing　temperature　but　little　on　the　melting　point.　By　adding　0.7　wt%　of　10　nm　SiO2　particles,　the　heat　of　fusion　and　the　decomposing　point　of　the　base　salt　were　increased　by　maximum　99.19%　and　68.4　degrees　C　respectively.　In　addition,　densely　dendritic-like　networks　were　observed　with　Scanning　Electron　Microscopy　in　the　nano-bromides　and　considered　to　be　responsible　for　the　improvement　of　the　heat　of　fusion　and　the　decomposing　point.　The　authors　believed　these　findings　would　contribute　to　enhance　the　heat　transfer　performance　of　heat　pipes　furtherly.