Abstract: Topological insulator（TI） is a new kind of material which is well concerned in recent years.The surface topological magneto-electric effect is the manifestation of its topological property.When a TI slab is plated with parallel magnetized ferromagnetic materials on both surfaces and treated as a defect in one dimensional（1-D） photonic crystal,we find a lot of new characters caused by the magneto-electric effect,such as the ’double 0.5 transmissions’ in the gap which is different from the normal defect when a linearly polarized light is normally incident,and the transmitted light can be left-and right-handed circular polarization at the double 0.5 transmissions frequencies respectively.The frequency difference between the double 0.5 peaks has been found to be modulated by different parameters of photonic crystal.From these new characters we can research the surface state of TI,as well as the fine structure constant.