DescriptionGraphene-reinforced polymer matrix composites offer high mechanical properties and have a wide range of potential applications including structural reinforcement materials, biomedical applications, packaging materials etc. The present study investigates the effect of the addition of graphene into the polyetheretherketone (PEEK) matrix. Graphene-reinforced polymer matrix composites (G-PMCs) were prepared using a high shear in-situ method with good particle-matrix adhesion of graphene at 2 wt.% and 35 wt.% in PEEK. The impact strength and the morphology of neat PEEK, 2% G-PEEK and 35% G-PEEK were characterized using Izod impact testing and by scanning electron microscopy (SEM). It was found that the impact strength of graphene reinforced PEEK is higher than neat PEEK at all degrees of exfoliation.