A crystalline sample of organic-inorganic cation exchanger acrylamide aluminumtungstate has been synthesized. The material behaves as a mono-functional cation-exchanger with an ion-exchange capacity 1.25meq/g for Na+ ions. The material has been characterized on the basis of thermal stability, chemical stability, FTIR, TGA-DTA, X-ray, and SEM studies. The effect of time and temperature on the distribution coefficient of metal ion was studied. It was concluded that 30 degrees C appeared to be the most favorable temperature. Sorption behavior of the metal ions was studied in different solvent systems. On the basis of distribution studies, the material was found to be selective for Pb2+ ions. Its selectivity was examined by achieving some important binary separations like Mg2+-Pb2+, Hg2+-Pb2+, Ca2+-Pb2+ Zn2+-Pb2+, Ni2+-Pb2+, and Al3+-Pb2+. The practical applicability of the cation-exchanger was demonstrated in the separation of Pb2+ ions from a synthetic mixture.