PURPOSE: To provide a cryogenic refrigerating device with a simple structure and high refrigerating capability.

CONSTITUTION: A heat exchanger for radiation 19 which is adjacent to the high temperature end 18 of a pulse tube 17 is connected between the previously mentioned pulse tube 17 and a buffer tank 20, and at the same time, the inside of the heat exchanger for radiation 19 is constituted into a porous state. The porous structure of the heat exchanger for radiation 19 substitutes the function of an orifice valve, and the orifice valve can be omitted, and at the same time, the refrigerating capability of a cryogenic refrigerating device can be increased by increasing the radiation function.