This paper demonstrates the designing and fabrication process of a W-wave polarizer with fine metal wires. The wires were designed to be 100 μm in diameter and 300 μm between each other. The mean values of these two parameters of the fabricated wire are 100.3 μm and 300.2 μm, with the standard deviations 5.2 μm and 8.3 μm respectively. Results show that the polarization grid has high fabrication precision and uniformity, and the polarizer surface flatness is better than 30 μm. In addition, the power transmission coefficient was measured. The actual measurement results and theoretical calculation results agree with each other perfectly. The polarizer fabricated by this new method has excellent performance.