A novel perfluorooctyl-containing triazine pyridine quaternary ammonium salt was designed and synthesized, which was applied to cotton fabrics by pad-dry-cure process. The treated fabrics showed good water and oil repellency, and washing durability. The water and oil repellent ratings were 100 and 6 respectively, and after 10 washing cycles, the water repellent rating was 90 and the oil repellent rating was 5. The modified specimen had the ultra low critical surface energy and showed excellent repellency to selected liquids (water, tea, milk, wine, machine oil, and wooster sauce). (c) 2006 Wiley Periodicals, Inc.