Provided is a breathing nose mask system, which comprises a nose mask for coming into close contact with the face of a user and for acting as means for introducing a breathing positive-pressure gas into the nose of the user, a frame for holding the nose mask in a predetermined position, and a headgear to be worn on a head for bringing the frame and the nose mask into close contact with the face. The breathing nose mask system is characterized in that the head gear includes at its leading end a head gear strap for adjusting the length of the head gear, in that the head gear strap includes a head gear fastener for acting as means for connecting/disconnecting means the frame, in that the frame includes a fastener catch for engaging with the head gear fastener, and in that the fastener catch includes a guide made rotationally symmetric on the axis (or rotation) in the direction to receive the head gear fastener. The breathing nose mask system can connect the head gear easily at the wear starting time, can prevent the twist of the head gear being worn, and which can be easily removed at a daily washing time.Linvention concerne un système de masque respiratoire nasal comportant un masque nasal destiné à venir étroitement en contact avec le visage dun utilisateur et à agir comme moyen dintroduction dun gaz sous pression positive de respiration dans le nez de lutilisateur, une armature destinée à maintenir le masque nasal dans une position prédéterminée et un accessoire de tête à porter sur la tête afin damener larmature et le masque nasal étroitement en contact avec le visage. Le système de masque respiratoire nasal est caractérisé en ce que laccessoire de tête comprend à son extrémité avant une sangle daccessoire de tête servant à régler la longueur de laccessoire de tête, ladite sangle comprenant une attache daccessoire de tête destinée à faire fonction de moyen de connexion / déconnexion de larmature, larmature comprenant un fermoir dattache destiné à coopérer avec latt
