The effect of sterilisation of Al2O3(by radiation, thermal treatment and in the autoclave) on its adsorption capacity and efficiency of elution of99mTc has been investigated. No difference has been observed in the adsorption capacity of sterilised and unsterilised Al2O3samples. However, efficiency of elution of99mTc differed in sterilised and unsterilised samples, and even depended on the sterilisation procedure used. The highest elution efficiency was found with unsterilised Al2O3(94%), somewhat lower with thermally sterilised (90%) and the lowest with60Co gamma radiation sterilised Al2O3(85%). Al2O3sterilised at 300°C has slightly higher adsorption capacity with respect to molybdenum.