The light-path bending phenomenon in filling-factor graded wavelike two-dimensional (2D) photonic crystals (PC) is due to the gradual modifications of the band structure and iso-frequency surface. Because of the band structure difference between TM and TE mode, the light-path bending phenomenon is polarization dependent, which is suitable for the polarization splitter in the normalized frequency a/λ region from 0.29～0.33. In the U-shaped bending waveguide of TM mode, the position of the emergent light is very sensitive to the incident wavelength and incident angle. The simulations with finite-difference time-domain (FDTD) method show that the sensitivities are 0.38 μm/10 nm and 0.29 μm/(°), respectively. The plane-parallel resonant cavity is built up in theory with the U-shaped bending waveguide for TM mode. The beam splitting and convergence effect are also discussed for the structure composed of filling-factor graded wave-like 2D-PC and one-dimensional multilayer thin films. This kind structure has the potential application in the plane-parallel resonant cavity.