Cellular micropatterning has become an important tool to precisely design cell-to-substrate attachment for cell biology studies, tissue engineering, cell-based biosensors, biological assays, and drug screens. This paper describes a new technique for micropatterning of cells that is based on the use of oxygen plasma as a patterning tool. The technique consists of (1) homogeneously grafting a glass substrate with a protein-repellent interpenetrating polymeric network (IPN) of poly(acrylamide) and poly(ethyleneglycol) [P(AAm-co-EG)] prepared with commercially available reagents and (2) selectively removing this coating using oxygen plasma. We use elastomeric stencils (i.e. self-sealing membranes with through-holes) and microchannels as removable masks for the selective oxygen plasma etch of the IPN areas that are not protected by the mask. The stencil or microchannels are peeled off to reveal cell-adhesive regions separated by the nonadhesive coating. Our method offers a convenient way of patterning a robust protein-repelling material, allows for independently controlling the chemistry of the regions reserved for cell attachment, and can be used to create coculture systems.