Purpose ‐ In this study, the polyester fabrics were treated with low temperature plasma before Cu sputtering. The effect of oxygen gas plasma pre-treatment on the surface structures, electrical properties, and mechanical properties of samples was investigated. The paper aims to discuss these issues. Design/methodology/approach ‐ A laboratory direct current (DC) magnetron sputter coating system was used to deposit the nanoscale copper (Cu) films onto the surface of polyester plain fabric at room temperature. Findings ‐ The crystal structure of the sputtered copper films did not show any obvious change on the O2-plasma-treated fabric, but the surface roughness and surface particle size increased significantly. Improvement in electrical properties of copper films was closely related to the deposition time. The tensile test results indicated that the mechanical properties of the plasma-treated polyester fabrics were also improved after copper coating. Originality/value ‐ The research reports on the functional textiles, and the experiment results and analysis are original. There is a great potential to commercialize such functional textiles.