Carbon nanomaterials are widely used as reinforcements in polymer composites, wherein small additions could lead to significant enhancements in mechanical, electrical and thermal properties. Binary combinations of three carbon nanomaterials with different geometric shapes: sphere-like 0D Carbon Black (CB), rod-like 1D Carbon Nanotubes (CNTs) and sheet-like 2D Graphene Nanoplatelets (GNPs) were explored for possible synergistic effect in epoxy composites. Mechanical and electrical properties of these hybrid filled epoxy composites were investigated. A synergetic effect was observed for the CNTs/GNPs hybrid filler system in terms of the flexural modulus and strength. Also a lower percolation threshold for electrical conductivity was obtained for the same CNT/GNP hybrid filled composite. The state of dispersion was evaluated at different length scales by different techniques. The results suggest that GNPs could improve CNT dispersion in the epoxy matrix, which may explain the observed synergy effects.