Abstract: A method of and apparatus for pelletizing a radioactive waste powder is disclosed. The apparatus includes a pelletizing section, and a pelletizing die which has one end facing a powder receiving cavity formed in the pelletizing section and the other end exposed to the atmosphere, and a through bore is so formed in the die as to pass from the one end to the other end. A first pelletizing rod can be inserted into and pulled out of the through bore from the one end of the die through the cavity, and a second pelletizing rod can be inserted into a pulled out of the through bore from the other end of the die. The first and second rods are arranged such that, when the second rod takes a predetermined position in the through bore, the first rod is inserted through the receiving cavity into the through bore, thereby enabling the pelletizing operation of the powder within the through bore.