Based on the concept and the treating techniques for photonic crystals, the characteristics of the forbidden band structures in one dimensional reflection hologram are analyzed. It is treated in the consideration of the reconstruction beam being incident to reflection hologram at different incident angles. The analysis shows that, for oblique incidence, the structures of forbidden band in hologram are slanted. For normal incidence, the structures of forbidden band in hologram are unslanted, and it is the special case of oblique incidence.