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Through-the-thickness stitching of layered composites provides through-the- thickness reinforcement to enhance the interlaminar tensile and shear strengths while maintaining structural continuity. However, under planar mechanical loads, stitched composites develop strain concentrations in the resin rich areas around the stitch seam causing a local reduction in mechanical properties. In this study, nanographene toughened epoxy is used to reduce strain concentrations around stitch seams and increase the global tensile performance in stitched composites. Stitched carbon fiber preforms ([+45/-45] ), infused with an unmodified epoxy resin were used as baseline laminates and compared to specimens infused with an epoxy resin containing a dispersion of 9 nm nanographene platelets. Specimens with two different periodic stitching patterns (0o and 90o) were fabricated and tested under uniaxial loading. The surface strain fields were obtained using digital image correlation (DIC). Noticeable differences were seen in the strain distributions and tensile properties of these test articles. Specimens with the nanographene-modified matrix showed reductions in the strain concentrations around the stitch seams, thereby increasing the local modulus of elasticity. This study presents the influence of nanographene-modified matrix on the tensile response of stitched composites