To provide a heat exchanger for multistage compression type refrigeration cycle device, which is miniaturized by incorporating a first radiator and a second radiator to a multiflow heat exchanger in an integrated manner.

In the heat exchanger for multistage compression type refrigeration cycle device comprises the first radiator for cooling primarily compressed refrigerant and the second radiator B for cooling secondarily compressed refrigerant, the first radiator A and the second radiator B are formed as an integrated unit by the multiflow heat exchanger 10 including a pair of headers 11 and 12 for dividing or combining the refrigerant, a plurality of refrigerant distributing heat exchanger tubes erected at intervals between the headers 11 and 12 and a heat exchanger fin 14 interposed each between the heat exchanger tubes 13. According to this structure, the setting space of the first radiator A and the second radiator can be minimized.