Wool fabrics were treated with low temperature oxygen plasma and/or protease, and examined for their mechanical and dyeing properties. By plasma-treatment the strength of wool fabric increased and higher rate of weight loss for protease treatment was obtained. When dyed by levelling type acid dye equilibrium dye uptake appeared same, but rate of dyeing increased by the plasma treatment, while, with milling type acid dye, both of them increased greatly in the order of untreated<protease-treated<plasma-treated>plasma/protease-treated. It was assumed from the above results that plasma affects the surface of fiber, and enzyme attacks mainly the inner part of fiber. This was confirmed again by scanning electron microscope.