We present a multi-channel PCs polarization filter, which overcomes the disadvantage of the low channel numbers in the existing filters. The multi-channel PCs polarization filter is based on one dimensional photonic crystal with a defect layer. The simulation results by transfer matrix method show that the filter can realize more than four filtering channels with the separation degree better than 0.95 and the transmission rate more than 50%, and the channels are almost distributed evenly. We also analyze the influence factors of filter performance. The results show that defect layer thickness of photonic crystal determines the number of filter channels. The thickness and number of unit layers of photonic crystals does not affect the number of filter channels, however it can adjust the location of central wavelength for each filter channel.