Rhenium-188 has been determined to be a suitable therapy radiolable due to its unique half-life and beta(-) emission associated with 155 keV photons and chelation properties. Re-188 is obtained from the decay of parent W-188 in the form of a genera tor system while W-188 is produced by double neutron capture of W-186. Th, yield of generators using alumina for separation is limited due to the low sorption capacity of sorbent. We have exploited precipitation as hydrous tungsten oxide in acid media and redissolution in alkaline media to separate Re-188 from tungsten. The optimized experimental conditions indicate the feasibility of a generator system based on this method.