Without any preprocessing, silk fabric has lower ability to hold on water due to the smooth morphology of silk fibers. Therefore, patterns directly printed with pigment inks have poor color yields and easily bleed. Plasma surf ace-treatment of silk fabric was carried out in an oxygen atmosphere under different experimental conditions. The samples were printed with magenta pigment ink after treatment. The results showed that the optimum treatment conditions we obtained were exposure time of 10 min at a working pressure of 50 Pa and a working power around 80 W. At such conditions, surface-modified silk fabrics could obtain the effects of features with enhanced color yields and excellent pattern sharpness. Atomic force microscope images indicated that low-temperature oxygen plasma initiated modifications to the surface of silk fiber with more grooves. Dynamic contact angle analysis showed that the hydrophilicity of silk fiber was remarkably improved after pretreatment with plasma. (c) 2007 Wiley Periodicals, Inc.