In this paper, a binary blazed grating-based polarization independent filter on silicon on insulator (SOI) under full conical incidence is presented. The properties of the grating filter are investigated by rigorous coupled-wave analysis. It’s shown that the filter demonstrates high reflectivity (R>99%) at its resonant wavelength, which stays the same under three different polarization states. It indicates that this grating filter is polarization-independent. The final data shows its polarization-dependent loss (PDL) is only 0.04 dB and the full width at half maximums (FWHMs) of the transverse electric (TE-) and transverse magnetic (TM-) polarized light are 0.24 and 0.46 nm, respectively.