We report a simple patterning method for single-walled carbon nanotubes (SWCNTs) films on flexible, transparent poly(ethylene terephthalate) using ail O-2-plasma technique in a capacitively Coupled plasma (CCP) system. The homogeneous SWCNT films in a large area were fabricated by the vacuum filtration method. The plasma patterning process of SWCNT films includes conventional photolithography and subsequent O-2-plasma treatment. During the plasma treatment, SWCNTs underneath the patterned photoresist polymer are protected front etching and damage by O-2-plasma while the exposed SWCNTs are destroyed. The morphological changes and the effect of plasma treatment on the chemical properties of SWCNT films were investigated by scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. The physical properties of SWCNT Films such as transparency and conductivity were systematically characterized under various plasma conditions. In ail electrochemiluminescence reaction, the SWCNT films patterned by the CCP system-based O-2-plasma treatment could be used as flexible and transparent electrodes.