Graft polymerization of vinyl monomers was made onto some natural and synthetic textile fibers that were pretreated by glow discharge plasmas. Among the monomers investigated, 2-hydroxyethyl methacrylate (HEMA) produced the most improved grafting effects. Effects of plasma gas source, exposing time of glow discharge, grafting time, temperature, etc., on grafting were investigated. Postpolymerization in vacuum allowing oxygen shutoff was desirable for improved grafting yield. Air exposure of the plasma pretreated textile fabrics lead to decrease of grafting yield prominently because of the deactivation of radicals by oxidation. Grafting amount was dependent also on the nature of the substrate textile fibers, and cotton was, in general, more reactive. Breaking strength of yarns increased after graft polymerization of HEMA, while the strength decreased by etching of yarns by plasma treatments using nonpolymerizable gas species. Increase of the strength in the grafted yarn is attributed to binding effect of the grafted polymers as revealed from studies of morphology by scanning electron microscopy.