A breathing mask for covering the nostrils of the user and supplying humidified breathing gas comprises:- a first member, for example a cushion (30), which abuts the face of a user and covers the nostrils, and comprises a first port (32) which takes in gas for breathing； and- a second member, for example a frame (20), having a rigidity greater than that of the first member, which covers at least a portion of the first member and comprises a second port (22) connected to a means, for example tube (28), for transport of the gas for breathing and which mates with the first port portion；wherein a cavity (40) is present between the first member and the second member to form a heat insulating air layer, so that condensation can be suppressed.
