AbstractA systematic study was made to prepare technetium‐99mgenerator for domestic uses in the fields of nuclear medicine and biological tracer work by using molybdenum‐99 produced by Tsing Hua Open‐pool Reactor (THOR). Alumina was used as generator bed and technetium‐99m was milked by physiologic saline solution. It was found that it is feasible to prepare technetium‐99m generator by which medically acceptable technetium‐99m solution can be obtained for practical a