The molecular dynamics simulation was utilized in this work to unravel the interfacial regulatory mechanisms of graphene coatings on NiTi shape memory alloys at the atomic level. The results demonstrate that graphene coatings significantly improve the tribological properties of NiTi through interfacial load transfer and stress buffering effects, in which the bilayer graphene (NiTi_2Gp) possesses excellent tribological properties, and its indentation force and hardness improve with the increase of the number of layers, but the excessive number of layers will lead to a decrease in the lubrication efficiency. The graphene coating expands the distribution region of von Mises stress, thereby effectively alleviating stress concentration while promoting martensitic transformation to enhance surface hardness. Elevated temperature intensifies wrinkling at the contact edges of graphene, compromising elastic deformation, impairing interlayer sliding capability, inhibiting martensitic transformation, and promoting the expansion of amorphous regions. These synergistic effects resulted in increased friction coefficients and diminished wear resistance. The study confirms that the friction mechanism shifted with temperature: it is dominated by reversible martensitic phase transformation at low temperatures and transformed into irreversible amorphous plastic deformation at high temperatures. This research provides a theoretical basis for the structural design and performance optimization of graphene coatings on NiTi alloy surfaces.