A new method has been developed for separation and purification of fission ⁹⁹Mo from neutron activated uranium aluminum alloy.Alkali dissolution of the irradiated target(100mg)results in aluminum along with ⁹⁹Mo andafew fission products passing in to solution,while most of the fission products,activation products and uranium remain undissolved. Subsequent purification steps involve precipitation of aluminum as Al(OH)₃, iodine as AgI/AgIO₃ and molybdenum asMo-α-benzoin oxime. Rutheniumis separated by volatilization as RuO₄ and final purification of ⁹⁹Mo was carried outusing anion exchange method. The radiochemical yield of fission ⁹⁹Mo was found to be > 80% and the purity of the product was in conformity with the in ternational pharmacopoeia standards.