The objective of this study is to investigate the effects of different nanoparticles as reinforcement in a polymeric matrix on the mechanical and tribological properties of the composite. The different particles including nanoclay (NC), nano-graphene oxide (NGO), and carbon nanotubes (CNT) with various weight percentages were incorporated into the epoxy matrix. Young's modulus, ultimate tensile strength, strain at the fracture point, and the fracture toughness of nanocomposite samples were investigated. Besides, the tribological performance of these fabricated nanocomposites was evaluated and discussed. The results show that a significant change in the mechanical properties of the nanocomposites compared to the epoxy matrix. Also, the results reveal that the combination of NC with NGO improves the mechanical properties of graphene nanocomposites. It is found that adding NC to the NG/epoxy composite, may increase the fracture toughness up to 2 times as well as improve the ultimate tensile strength and strain at the fracture point. However, there was no significant change in Young's modulus.