A modified sorbent for99mTe generators of higher activities has been developed. The sorbent consists of two layers. The layer in which (F.P.)99Mo is adsorbed contains alumina and silica gel mixture in the weight ratio 4060%. The underlaying layer contains 0.5% g of pure alumina. The performances of the columns filled with this sorbent are compared to these containing pure alumina with respect to the total elution efficiency of99mTc and the elution efficiency ratio of subsequent elutions. Radiochemical and radionuclidic purities (99Mo breakthrough) of eluates from both kinds of columns have also been determined and compared.