A filter device of the present disclosure includes at least a sheet-shaped fiber structure having a plurality of fibers made of amorphous silicon dioxide, wherein the plurality of fibers are tangled and thus connected together to form voids in the sheet-shaped fiber structure. A filter device of the present disclosure corresponds to an analysis device including: a substrate; a flow path formed on the substrate; and a sheet-shaped fiber structure provided on the inner wall of the flow path, wherein the sheet-shaped fiber structure includes a plurality of fibers made of amorphous silicon dioxide, and the plurality of fibers are tangled and thus connected together to form voids in the sheet-shaped fiber structure.