Due to the low cost and high safety of the new sodium battery system using sodium-based solid electrolyte, the new sodium battery system has great potential for its applications in energy storage field. High ionic conductivity and stability of sodium-based solid electrolytes are prerequisites for its applications in new sodium battery systems. In recent years, people have significantly improved the ionic conductivity and stability of sodium-based solid electrolytes by improving preparation methods and doping modifications. In addition, the new sodium battery system needs to solve the interface problems such as poor interface contact and poor interface stability between the solid state electrolyte and the electrode. In this paper, we firstly summarize the research progress in ionic conductivity and stability of β″-Al₂O₃, NASICON, sulfides, and polymer of sodium-based solid electrolytes. Then the applications of sodium-based solid electrolytes in sodium-sulfur batteries, hybrid sodium-air batteries, and all-solid-state sodium-ion batteries are introduced. In view of the interface problems, the solving strategies are systematically discussed. The future large-scale applications in energy of the new sodium battery system based on solid state electrolytes need breakthroughs in many aspects such as battery materials, interfaces, and battery design.