To improve the ease of use of a humidifier capable of humidification with electrolyzed water.

In the humidifier 1, there are arranged in a casing 10 a humidification filter 17 which is put in a wetted state with the electrolyzed water in an electrolyzed water generating part 22, and a blower 16 generating an air flow passing through the humidification filter 17. A water supply tank 31 for supplying water to the electrolyzed water generating part 22 is held on a tray 30, and on the under face of the tray 30, there are provided wheels 65 on the near side, first ground-contact legs 66 contacting with the floor of a water supply tank containing space 26 in the casing 10 and second ground-contact legs 67 contacting with the face supporting the casing 10 on the back side. In the first ground-contact legs 66 and the second ground-contact legs 67, when ones of them are in a contacting state, the others are in a floating state. The friction coefficient of the contact faces of the second ground-contact legs 67 is set higher than the friction coefficient of the contact faces of the first ground-contact legs 66.