<p>A multi-tube type heat transfer apparatus including a plurality of heat transfer tubes disposed in parallel to each other within a shell wall is improved. A plurality of holes (10) having a larger diameter than the outer diameter of the heat transfer tubes (1) are provided in each of a plurality of baffle plates (5) disposed at intervals within the shell wall (11). The heat transfer tubes extend through the respective holes. A flow passageway of fluid on the side of the shell is composed of annular spaces formed between the outer circumferences of the heat transfer tubes (1) and the inner circumferences of the holes (10) in the baffle plates. Preferably the inner diameters of the plurality of holes in the respective baffle plates are distributed, and thereby the cross-section areas of the flow passageways of the fluid on the side of the shell between the outer circumferences of the heat transfer tubes and the inner circumferences of the holes in the baffle plates are distributed.</p>
