To provide a humidifier for a retractable toilet which can dry and humidify the toilet in a short time immediately before use and is free from requiring installation space.

An opening/closing lid 3 is pivotably mounted in a front opening 2 of a humidifier body 1 so as to shift from an erectly closed state to an opened state which is forwardly tilted. The opening/closing lid 3 is provided with a door pocket 7 on the inner side thereof. When the opening/closing lid 3 is shifted to a tilted state, the retractable toilet 8 is supported by the door pocket 7. A device 12 for blowing out a hot air which has a supply opening 17 facing the retractable toilet supported by the door pocket is provided within the humidifier body 1.