Abstract In this study, Cu-based nanocomposites using nanographite, graphene nanosheet and carbon nanotubes have been fabricated by flake powder metallurgy. The objective of using different reinforcement contents is to assess their effect on the microstructure, density, electrical conductivity and hardness of Cu-based nanocomposites. The results show that the average particle size of the prepared Cu-based nanocomposite powders with reinforced 5 wt.% nanographite, graphene nanosheet and Cu-CNT nanocomposite are 97.8, 94.9 and 49.7 μm, respectively. The lowest final density 6.73 g/cm3 for sintered Cu-5 wt.% CNT nanocomposites, while the highest density value was 8.78 g/cm3 for sintered Cu-0.5 wt.% nanografit nanocomposites. For all nanocomposite groups, increasing the reinforcement content from 0.5 to 5 wt.% results in an decrease in hardness values. The electrical conductivity of the Cu-0.5 wt.% graphene nanosheet was approximately 79 IACs, and this value decreased slightly to 62 IACs with increasing graphene nanosheet content.