The present invention relates to a sodium-sulfur battery consisted of solid sodium for the negative electrode (comprising carbon, sodium metal oxide and the like comprising sodium compound, sodium ion); solid sulfur for the positive electrode (comprising sulfur, sulfur compound such as iron sulfide, nickel sulfide); and liquid electrolyte which sodium salt and organic solvent such as grymids or carbonates are soaked in cell guard, thereby improving a drawback of prior art for conventional battery.