A structure fixing apparatus for attaching a structure on roof tiles, for example, the structure being a solar cell apparatus, includes a support device for supporting attachment hardware which is a part of a base for fixing a solar cell module, a fixing member formed to reach a sheathing through the support device and a roof tile, and a tubular portion formed to surround the fixing member and to be inserted in a through hole formed in the roof tile. The tubular portion is formed to be smaller in size than the through hole formed in the roof tile and to be in non-contact with the through hole.