This research of using cationic surfactant KC-3A(Quaternary ammonium salt) modify C.I. Reactive Blue 19 (RB19) to the water dyeing process and dyeing polyester、nylon 6.6 and Tencel (a kind of cellulose) fibers with supercritical fluid dyeing method. The modify dye (MRB19) structure determined by FT-IR. RB 19 and MRB 19 were dyed polyester、nylon 6.6 and Tencel fiber in exhausting dyeing process. The results were found it maybe dye these fibers with good fastness properties and to acceptable color depth. The positive effect of long alkyl of Quaternary ammonium salt modify dye is due to an effect of increased molecular weight and due to an effect of reactive groups on the reactivity of the dye–fiber system to diminish where the alkyl chain increases the hydrophobicity of the dye. The experimental result showed the dyeing with MRB 19 dye of nylon 6.6 and polyester fibers are satisfactory by dyeing in supercritical carbon dioxide with good fastness properties and accept color depth. Besides, Tencel was dyed by supercritical carbon dioxide with pre-treatment of the fiber the color depth was higher than the other on water dyeing process. For Tencel fiber, optimum dyeing results are obtained at 140 ℃（300 bar）；nylon6.6 fiber, optimum dyeing results are obtained at 120 ℃（300 bar）；polyester fiber, optimum dyeing results are obtained at 120 ℃（250 bar）. The wash and rub fastness of all dyed fibers were rated at between 3-4 and 5. Keywork：Cationic、Vinylsulphone、Supercritical Fluid、Reactive Dyes、Hydrophobic.