To retard an increase in gas flow resistance even if gas passages in superposed blocks become eccentric in a heat accumulator for a regenerative combustion type deodorizer.

A regenerative combustion type deodorizer is so designed that each heat accumulator 7 repeats a phase of temperature reduction when it heats low temperature gas before deodorization passing gas passages and a phase of temperature increase when it is heated by high temperature gas after deodorization passing the gas passages, and comprises the superposed blocks 9 with many through gas passages, and that the gas passages of the heat accumulator 7 are defined by the connection of the gas passages of the superposed blocks 9. According to a gas passage mechanism for a heat accumulator, the heat accumulator 7 has a meshed wavy board 11 such as wire gauze interposed between one block 9 and the next block 9 superposed, and each gas passage in one block 9 in connected to a plurality of gas passages in the next block 9 via meshes of the meshed wavy board 11 and gaps between the meshed wavy board 11 and the blocks 9.