Abstract: A heat and moisture exchanger includes: a heat and moisture exchanger material formed by coiling a strip-shaped porous body, the porous body having a plurality of slits formed therein that are arranged along the lengthwise direction, into a spirally-wound shape with the slits facing radially outwardly; and a housing that accommodates the heat and moisture exchanger material. Such a structure for an HME makes it possible to reduce pressure loss and improve moisture retention capabilities by means of a relatively simple structure, thereby allowing the inexpensive provision of an HME that lowers the burden on a patient.