Over last ten to twenty years, a lot of work is carried out on applications which used heat pipes for heat transfer. These heat pipes were carrying conventional fluids as working medium inside them. But in recent years, experiments have been carried out to use suspended nano sized particles into conventional base fluids to enhance the thermal conductivity of heat pipes. It has been found that the nanofluids are responsible for effective heat transfer. In this paper the basic work of heat pipe nanofluids and the effects of nanofluid concentration on performance of heat pipe are discussed. The studied results have shown a remarkable influence on decrease in thermal resistance of the heat pipe wall.