Extensive research has gone into enhancing the thermal efficiency of heat pipes using conventional fluids for over a decade. The enhanced thermal properties of heat pipes using nanofluids has also been researched upon by various researchers over the past few years. The study shows that the thermal characteristics of the heat pipe are enhanced using nanofluids in comparison to conventional working fluids. This paper summarizes our research on the thermal effect of four different nanofluids in heat pipe and identifies the possibility of nanofluid that can be successfully used to improve thermal efficiency of heat pipes. © IAEME Publication.