Abstract: The effect of the arrange of LC molecular on the transmission spectrum in the one-dimensional photonic crystals of a turn of the TiO2 and SiO2 dielectric film was studied, parallel and twist, respectively. It appeared four transparent peaks in photonic band gap when parallel orientation of the nematic LC, the central wavelengths were approximately at 1 840, 1 814, 1 466 and 1 423 nm. Then heating the device, the peak position would blue shift, and the adjacent transparent peak would overlapping. It appeared two independent transmission peaks in photonic band gap, whose position were at 1865, 1489nm, respectively, when twist arrange of the nematic LC. Heating sample, the peak position appeared blue shift. The refractive index anisotropy was more pronounced in the nematic LC layer of the parallel orientation and had two polarization transparent peaks. However, with the twist arrange of the nematic LC, refractive index anisotropy was not obvious, photonic band gap only had one independent transparent peaks. LC molecular orientation could be changed when heating sample, and causing the effective refractive index of the LC layer change, so that to move the position of transparent peaks.