Density functional theory calculations, including dispersion effects, are used to demonstrate how substitutional nitrogen atoms can improve the catalytic reactivity of graphene nanoribbons (GNR) with edge defects in the CO oxidation process. It is demonstrated that the addition of nitrogen impurities significantly enhances O2 adsorption on GNR. Carbon atoms near the edges of defects are the most active sites for capturing O2 molecules. The lower adsorption energy of CO relative to O2 implies that the N-modified GNR is resistant to CO poisoning. The Eley-Rideal (E-R) mechanism has activation energies as low as 0.38 eV, making it the most energetically relevant pathway for the CO + O2 reaction. The findings of this study might help in the design of catalysts for metal-free catalysis of CO oxidation.