Graphene nanoplatelets (GNPs) have garnered significant attention in the field of thermal management materials due to their unique morphology and remarkable thermal conductive properties. Their impressive thermal properties make them an interesting choice of nanofillers with which to produce multifunctional composite materials and a host of other applications whilst their structural and thermal properties significantly improve their target materials or composites. Therefore, this present study reviewed recent advances in the use of GNPs as nanofillers to enhance the thermal conductivity of various materials or composites. The improved thermal conductivity that GNPs impart in composites is also comprehensively compared and discussed. Therefore, this review may reveal hitherto unknown opportunities and pave the way for the production of materials with enhanced thermal applications including electronics, aerospace devices, batteries, and structural reinforcement.