In order to investigate the influence of incident angle and impurity absorption on one-dimensional photonic crystal reflectors,the complex refractive index method and TFcalc software are adopted.The results show that the centre of the band gap moves to the short-wave direction horizontally,and the bandgap width gets narrower,as the incident angle increases.When the incident angle is below 60°,the depth of the band gap is almost unchanged,while the incident angle is over 60°,the depth of the band gap largely changed.As the incident angle gets close to 90° infinitely,the band gap for P polarization light nearly disappeared,however,the band gap for S polarization light almost reserved.When impurity absorption remarkably affects the transmissivity and reflectivity of the one-dimensional photonic crystal,the critical values of the extinction coefficient are 0.0003 and 0.001,respectively.The absorption of the high-refractive index films affects the spectra less.