Effective thermal management has become extremely urgent for electronics due to the massive heat originated from the ever-rising
power density. With the merits of high thermal conductivity, good chemical stability and desirable mechanical properties, carbon
nanotubes (CNTs) are considered to have great potential to be widely used in heat dissipation devices. This article describes the
progress on thermal conductivity of CNT-reinforced composites, aligned CNT materials (aligned CNT arrays, films/buckypapers
and fibers) as high thermal conductors, experimental and theoretical results of CNT-substrate interface resistance, and utilizations of
CNTs in the passive heat dissipation (natural convection, heat radiation, and phase-change heat transfer). Finally, the challenges
and prospects are discussed to provide some hints in the future studies. It is believed that CNTs can play an important role in
thermal management of electronics, especially in the portable electronic devices.