Effective heat transfer by heat pipe using nanofluid plays an important role in thermal management. Nanofluids are highly preferred for various thermal application because of its stability and high ability to transfer heat. Heat transfer enhancement of nanofluid depend on different parameters like thermal conductivity, volume concentration of particles, particle shape, mass flow rate in a heat pipe. Thermal conductivity may be affected by using composite nanoparticles for a constant volume concentration and mass flow rate. Composite (hybrid)nanoparticle is a mixture of two or more different material of nanosize .Hybrid particles are used to prepared hybrid nanofluid. The idea of preparing hybrid nanofluid is to achieve heat transfer enhancement in heat pipe with increased thermal conductivity. In this review paper the aim is to study the hybrid nanofluid and its effects on heat pipe thermal performance.