This work presents the use of an ultra-low-cost and flexible paper-based microplasma array to perform maskless patterning of poly(ethylene oxide)-like (PEO-like) thin films with a feature size down to submillimeter scale. In this process, the liquid precursor was directly applied to the paper substrate, gradually vaporized, and dissociated in the microplasma cavity, which leads to plasma polymerization. The FTIR and XPS spectra of the deposited film confirm the PEO-like structures. The protein adsorption test using the absorption of fluorescence-labeled fibrinogen conjugates on the treated surface shows the deposited films possessed the antifouling property with decent pattern transfer fidelity defined by the geometry of the microplasma array.