The effects of oxygen plasma treatments at different discharge power, reaction pressure, treatment time on yellowing of polyester fabrics were studied. Surface characteristics of the treated fabrics were also investigated by means of SEM and ESCA. The results were as follows : The yellowing of fabrics increases as the power and the treatment time are increased, and decreases as the pressure is increased. The plasma treatment of 100 Watt, 200 mTorr, 5 min. is the optimal condition which is most effective in holding whiteness as well as high weight loss of fabrics.