Graphene nanoplatelets (GNPs) reinforced 7075Al nanocomposites were synthesized by pressure sintering method. A novel method for optimizing interfacial bonding through TiO₂ coated GNPs was proposed. The effects of TiO₂ coated GNPs on mechanical properties and microstructure of the aluminum matrix nanocomposites were investigated. Results show that the mechanical properties of the nanocomposites are improved by addition of TiO₂ coated GNPs, compared with those of nanocomposites with pure GNPs. The yield strength, ultimate tensile strength, and microhardness of the nanocomposites reinforced by TiO₂ coated GNPs are increased by 38.9%, 34.4%, and 20.1%, respectively, compared with those of the matrix. The improvement of the mechanical properties is attributed to the coating layer, which optimizes the interface bonding between the reinforcement and the matrix, thereby improving the efficiency of load transfer.