A systematic study was conducted using argon, oxygen, and nitrogen plasma to improve the adhesion of polypyrrole coating to polyester (PET) fabric for improving conductivity and to understand the mechanisms involved. PET thin film was used as a reference sample. The changes in wettability, surface chemistry and morphology were studied by water contact angle, X-ray photoelectron spectroscopy, and atomic force and scanning electron microscopy. It was found that both the highest conductivity and the strongest interfacial bonding were achieved by oxygen plasma treatment. The increase in hydrophilicity, surface functionalization, and suitable nano-scale roughness gave improved adhesion.