Nanoscale carbon materials, including fullerenes, carbon nanotubes, graphene nanosheets, and small carbon nanoparticles, have interesting and/or unique properties. We have been studying these nanomaterials, from fullerene conjugates with anticancer drugs and bulkseparated metallic/semiconducting single-walled carbon nanotubes for electrical/electronic materials and applications to more recently graphene nanosheets for thermal and mechanical nanocomposites and carbon-based photoluminescent nanoparticles (“carbon dots”) as effective imaging agents. In this talk, some interesting and representative results from our research will be highlighted.