Abstract: The graft modification of PET film with acrylic acid initiated by microwave low temperature plasma was carried out and the best process conditions were optimized by varying the time,power,and gas pressure of the treatment.The washing effect of the polyester fabric was tested with these process conditions.The characterization of the fabric was performed by means of IR spectrum and SEM photographs.The results show that microwave low temperature plasma have an obvious etching effect on PET film and acrylic can be grafted onto the surface of PET film after plasma treatment.It proves that the surface modification of PET is feasible by direct acting to the material surface with the microwave low temperature plasma gas of acrylic acid.