Aluminum alloy AA2219-Graphene/MWCNT composites with near theoretical density have been successfully processed through high energy ball milling followed by spark plasma sintering. Effectiveness of varying content of Graphene and MWCNT as reinforcements was studied on different aspects of processing of the composites. The particle size increased during milling due to agglomeration but presence of reinforcement restricted the agglomeration process. Significant change in particle size of milled composite powders was not observed for the type (Graphene/MWCNT) or content (0.5–2 wt%) of the reinforcements. The increase of reinforcement (Graphene/MWCNT) content above 0.5 wt% resulted in lower hardness for spark plasma sintered composites. Further, both AA2219-Graphene and AA2219-MWCNT composites revealed similar hardness values. Finally, different aspects of processing (mechanical alloying, densification) and characterization (microstructure, hardness, electrical conductivity) revealed similar results irrespective of type of reinforcement i.e. Graphene or MWCNT. © 2017, The Indian Institute of Metals - IIM.