A considerable amount of work has been reported on isothermal annealing of pure alkali and alkaline earth metal nitrates. In the present work, initially, the eutectic of NaNO3-KNO3 was prepared by mixing NaNO3 (45%) and KNO3 (55%) fused at 225 0C and cooled naturally. The samples of a eutectic of NaNO3-KNO3 were irradiated in 60Co – gamma source. The radiation decomposition of the eutectic mixture takes place. Present work mainly deals with the study of isothermal annealing of radiation damage in a eutectic mixture of NaNO3-KNO3. This data has been analyzed by using conventional kinetics and the Waite model. Results of annealing show that a significant fraction of annealing obeys second order kinetics except in the initial short period. The energies of activation are calculated by two methods and are found to agree.