In this work, poly(ethylene terephthalate) (PET) films were treated by oxygen and helium plasmas and their chemistry and morphology were studied. Samples were characterized by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), scanning electron microscopy (SEM) and water contact angle (WCA) measurements. The aging of plasma-treated PET films was studied in different media (air and water) by WCA. The anti-fouling properties of the plasma treated surfaces were evaluated by confocal microscopy. Both oxygen and helium plasma-treatments produced hydrophilic and nano-structured surfaces that presented a remarkable reduction of the bioadhesive character. Besides, the grafting of plasma treated surfaces was explored using Pluronic F108 in order to improve the anti-fouling properties of the plasma treated surfaces.