A polished rutile TiO2 (001) surface was annealed at 410 °C and studied using low-energy electron diffraction (LEED) and surface X-ray diffraction (SXRD). The LEED pattern revealed a (1 × 1) structure. The crystal truncation rods (CTRs) obtained using SXRD were analyzed to reveal the structure of the annealed TiO2 (001) surface. We found that about 40% of the surface was flat and the remaining 60% consisted of facets. The facets were mainly {011}-oriented. They were three layers deep and contained no terraces. It was reported that TiO2 (001) surface annealed at 410 °C exhibited more moderate photocatalytic activity than the HF-treated surface. Comparing these results, it was concluded that the formation of {011} facet lowered the photocatalytic activity of annealed TiO2 (001) surface than as-received surface.