Molecular dynamics simulations were performed to investigate the mechanical properties of a single-crystal gold nanosheet and graphene nanoribbon-embedded gold (GNR/Au) composites for various embedded locations, temperatures, and lengths. The computational results show that the Young's modulus, tensile strength, and fracture strain of GNR/Au composites are much larger than those of pure gold. The mechanical properties of GNR/Au composites deteriorate drastically due to C-C bond breaking. Thermal fluctuation and an increase in length can decrease the mechanical properties of GNR/Au composites.