PROBLEM TO BE SOLVED: To facilitate the handling of the invention by a simple structure.SOLUTION: A humidifier 12 includes: a container 13 for storing liquid a feeding mechanism for feeding the liquid from the container 13 while reducing the content of the container 13 in time a permeable member 14 for vaporizing the liquid supplied from the container 13, the permeable member 14 being located in a suction pipe 11 for introducing air into a respiratory tract of a user of the respiration assistant device 1 and an injector 15 for injecting the liquid into the container 13, the injector being indirectly and detachably connected to the container 13.COPYRIGHT: (C)2015,JPO&INPIT