Abstract: Requirement for the radioactive source used in multiphase flow meter is that the overall shape dimensions must be fixed and the the maximum output rate of photons must be improved to 1.5 times more than the former. As the former preparation process can not satisfy the requirement, the composition of surface glaze was changed in order to reduce the self-absorption and improve the photons’ output rate, the ratio between surface glaze and Am-241 oxidizes was optimized, the input of radioactive material was increased,but the size of certain shape and active zone was fixed.The results showed that various kinds of technical index all satisfied demands of international standard and the feedback was good in sevice.