A heat exchanger is provided. The heat exchanger may include a shell; a first pipe that guides a first fluid into the shell; a plurality of spiral pipe portions, through which a second fluid, which exchanges heat with the first fluid, may pass, that have different distances from a central axis; and a second pipe that guides the first fluid outside of the shell, in which an inner spiral pipe portion of the plurality of spiral pipe portions, which is closest to a central axis, and an outer spiral pipe portion, which is farthest from the central axis, are connected by a first connection tube, and a plurality of intermediate spiral pipes, which is farther from the central axis than the inner spiral pipe portion and closer to the central axis than the outer spiral pipe portion, is connected by a second connection tube, such that the plurality of spiral pipe portions is connected while minimizing a number of connection tubes and a reduction in performance that may be generated when a difference in length of a plurality of paths is large, by minimizing a difference in length of the paths formed by the plurality of spiral pipe portions and the connection tubes.