Nanocomposite solders were prepared by adding graphene nanoplatelets (GNPs) and carbon nanotubes (CNTs) into the eutectic Sn-Ag-Cu solder alloy according to the mechanical alloying and compaction consolidation of the mixed materials. Then, the effects of graphene and nanotubes as reinforcing inclusions on the functional performance of nanocomposite solder materials were assessed. Variations in the melting temperature of solder alloy governing the incorporation of different graphene and nanotube contents can be ascribed to the compatibility of these carbon-based reinforcing agents with the alloy matrix without and in the contribution of nickel-coating modification. Also, these nano-sized materials' impact on the solder alloy's densification behavior and its wettability on the copper surface was assessed. The microstructural refinement of solder alloy with the dispersion of two GNPs and CNTs as the reinforcing agent with different wright fractions and corresponding textural evolutions were characterized by electron backscattered diffraction (EBSD) analysis in correlation with the mechanical response in terms of indentation hardness resistance.