To prevent fixation of a spare tire from being released without engaging an operation member with an operation member engaging part of a rotary shaft.

A spare tire holding device is constituted in such a way that a wire 30 constituting a tire pressing device 24 is wound up by operation of the rotary shaft 32 and a spare tire is pressed and fixed against a tire support member. A guide member 110 is provided to guide engagement of the operation member into an engaging recessed part 94 of the rotary shaft 32. The guide member 110 is made of synthetic resin, and an inner peripheral face of a guide part 114 is a guide face 116 guiding engagement with the engaging recessed part 94. The guide member 110 is rotatably held on the rotary shaft 32 in a cylindrical part 112. Consequently, the rotary shaft 32 cannot be rotated even if an attempt to grip and rotate the guide part 114 of the guide member 110 is made, thereby preventing theft.