To provide a rotary regeneration type heat exchanger capable of cleaning easily even when produced matters are generated at any part.

A rotary cylindrical heat transferring element 3 is constituted of a divided plate 10, consisting of a cylindrical surface divided in the circumferential direction into two parts so as to be concentrical with an axial center, and a divided partitioning plate 11, dividing a fluid passage formed in a duct 7 circumferentially so as to coincide with the division of the heat transferring element 3 into two parts forming introducing passages 12, 14 and discharging passages 13, 15. According to this method, heating fluid 51 is introduced from the inside (outside) of one of the rotary surface side of the heat transferring element 3 to discharge from the outside (inside) of the same rotary surface side while fluid 61 to be heated is introduced from the outside (inside) of the same rotary surface side to discharge it to the inside (outside) of the same rotary surface side whereby high-temperature part 3 (3) can be formed at the inside (outside) of one rotary surface side, low-temperature parts 1 (1) can be formed at outside (inside) and a medium temperature part (2) can be formed at the other rotary surface side.