Abstract: In order to study high performance filters based on photonic crystal waveguide, some methods such as adjusting the structures of resonant cavities and optimizing the coupling regions were adopted in the paper. Three kinds of bent photonic crystal waveguides were designed based on the coupled-mode theory in square dielectric rod photonic crystal. After theoretical analysis and experimental verification, the performance characteristics in the S-band and C-band were studied by the time-domain finite-different method. The results show that, 3 kinds of waveguides have good band stop or band pass characteristics at different wavelengths. Cutoff transmission wavelength and passband transmission wavelength shift toward longer wavelengths with the increase of relative dielectric constant of the overall dielectric column. Cutoff wavelength and transmission wavelength are increased by about 6nm with the increase of dielectric constant ε_r by 0.3. The study has potential value in the designs of micro optical sensors, micro optical communication devices, optical integrated circuits, etc.