[en] Radiation-chemical behaviour of palladium during its extraction from 3 mol/l HNO₃ solutions by TIAP solutions in n-dodecane was studied. The change in extractional behaviour of palladium depending on irradiation dose of two-phase system, containing organic 33% solution of TIAP in n-dodecane and aqueous nitric acid solution of Pd²⁺, was considered. It is shown that with an increase in the absorbed dose palladium distribution coefficient also increases. It is ascertained that the presence of palladium does not affect accumulation of acid products fro TIAP destruction. The influence of preliminary (prior to extraction) irradiation of aqueous and organic phases on palladium extractional behaviour was analyzed. Formation of precipitates containing palladium in case of its nitric acid solution contact with irradiated organic substance was recorded, conditions of the precipitate formation being studied