An organic electrolytic solution includes a lithium salt; an organic
solvent including a high dielectric constant solvent and a low boiling
point solvent; and an additive of a hetero ring compound including a
cyano group and an alkenyl group as substituents. The organic
electrolytic solution and the lithium battery employing the organic
electrolytic solution suppress the reduction decomposition of a polar
solvent to improve the capacity retention ratio of the battery. Thus, the
charge/discharge efficiency and lifespan of the battery can be improved.