The invention discloses a photonic crystal waveguide polarizing beam splitter which introduces a line defect to form a structure of a coupled waveguide in a two-dimensional tellurium dielectric rod photonic crystal, and implements beam splitting for TE beam and TM beam by using different coupled lengths of waveguides of the TE beam and the TM beam. The characteristics of the implementation of the polarizing beam splitter by adopting a two-dimensional photonic crystal waveguide are as follows: firstly, compared with the prior various polarizing beam splitter devices, the polarizing beam splitter adopting the two-dimensional photonic crystal waveguide can implement a polarizing beam splitting with high degree of polarization and high extinction ratio; secondly, the device can be provided with a smaller size, and can be structurally compatible with the prior photonic crystal device to meet a requirement of integration ratio; thirdly, the polarizing beam splitter adopting the two-dimensional photonic crystal waveguide has a very flexible structure, and can implement the polarizing beam splitting of any wavelength in a range from 3.5 to 35mu m for wavelengths through adjusting a length of a coupling region or a lattice constant. The invention also discloses a designing idea and a particular structural design of the polarizing beam splitter, an optical performance, etc. of the polarizing beam splitter acquired from the designing idea.