Molten　salt　has　been　extensively　applied　as　a　medium　for　heat　transfer　and　thermal　energy　storage.　In　this　work,　a　novel　quinary　nitrate/nitrite　mixed　molten　salt　is　developed　and　its　comprehensive　thermophysical　properties,　thermal　stability,　sensible　thermal　energy　storage　density　and　economics　are　evaluated.　Based　on　the　thermal　analysis　method,　the　melting　point　and　decomposition　temperature　of　the　NaNO3-KNO3-Ca　(NO3)2-NaNO2-KNO2　system　are　determined　at　102.3　degrees　C　and　651.2　degrees　C,　respectively.　Furthermore,　the　specific　heat　capacity,　density　and　thermal　conductivity　of　the　quinary　molten　salt　are　measured　using　specific　apparatus　with　satisfactory　results.　It　is　noteworthy　that　after　long-term　high　temperature　test　and　multiple　heating-cooling　cycle　tests,　the　change　rate　of　the　various　thermophysical　properties　of　the　quinary　molten　salt　is　all　less　than　10%,　exhibiting　excellent　thermal　stability.　The　sensible　thermal　energy　storage　density　of　the　quinary　molten　salt　is　743.7　kJ/kg,　and　the　sensible　thermal　energy　storage　cost　is　17.2　RMB/(kW　&　sdot;h).　Eventually,　the　proposed　molten　salt　has　the　advantages　of　the　wide　liquid　operating　temperature　range,　high　sensible　thermal　energy　storage　density　and　better　thermal　performance,　which　can　be　widely　used　as　an　excellent　heat　transfer　and　storage　material　for　thermal　energy　storage　systems.