N-methylmorpholine-N-oxide(NMMO) is recently hewn as a solvent dissolving cellulose to produce a new regenerated cellulosic fiber, lyocell. In this study, four kinds of cellulosic fibers (lyocell, regular cotton, treated cotton with 50% and 75% NMMO aqueous solution) was examined and compared in terms of mechanical properties and dyeability. The swelling of cotton treated with NMMO aqueous solution is higher than that of cotton treated with water. In dyeing rate, the cotton treated with NMMO was faster than regular cotton. NMMO treatment decreased the crystallinity of cotton fabrics and improved their softness and smoothness.