A disclosed cryogenic refrigerator includes a first refrigerator including a compressor, a regenerator which performs intake or ejection of a refrigerant gas relative to the compressor, and a pulse tube whose low temperature end is connected to a low temperature end of the regenerator; a second refrigerator having an output smaller than the first refrigerator; a connecting pipe which performs intake and ejection of the refrigerant gas relative to a high temperature end of the pulse tube and the second refrigerator; and a flow control valve which is provided in the connecting pipe and performs a flow control of the refrigerant gas flowing inside the connecting pipe.