We describe here the nanoscale hybrid architecture of polyethylene crystals directly nucleated on three different forms of nanostructured carbon, namely, carbon nanotubes, graphene oxide, and single-walled carbon nanohorns. The hybrid architecture exhibits structural stability such that they act as potential nucleants for subsequent nucleation and growth of polymer crystals. It is intriguing that the structural morphology of polyethylene crystals vary on the three forms of nanostructured carbon even though they are structurally similar. The underlying differences in structural morphology and the mechanism of crystallization are discussed. The intriguing observations open the gateway for effective utilization of different nanostructured carbon in a polymer matrix, without influencing their inherent properties.