The durability research on the filter media is of great significance. It is necessary to establish a laboratory test method on it in practical use. A new testing method is provided for filter media durability under corrosive gas condition in the paper. PPS is selected as standard testing sample and it is tested in NO gas. Under 1000ppmNO and 200°C condition, both warp strength and weft strength of PPS increase at the beginning and then gradually decrease with duration. The weft change for both strength and elongation is higher than the warp.