PURPOSE: To safely hold a tire even in the case of the tire being exploded by overinflation by providing a device for holding a tire placed on a table, in a detachable state, and a valve device for opening/closing an air conduit in relation to the tire according to the attaching/detaching position of the holding device.

CONSTITUTION: A tire changer has a base 11 and a tower 12. A vertical adjusting arm 16 with a tire attaching/detaching head 14 is fitted to the tower 12 through a horizontal adjusting arm 13. The tire 23 is placed on the upper face of a rotary table 26, and air is led in from an air conduit. In this case, a holding device 28 of the tire 23 is oscillatingly installed on the upper face of the base 11 through a bracket 32. One end of a belt 29 is connected to the holding device 28 through a locking device 46, and the other end of the belt 29 is connected to a winding device 31. The air conduit 54 is enclosed in a tube 33b of the holding device 28, and a valve device (unillustrated) is provided to open/close the air conduit 54.