Reaches in nanofluids heat transfer have conducted for decades, and lead to the development of the currently used heat transfer enhancement techniques. This paper is mainly concerned about the character of nanoparticles as an additive to the refrigeration system, and the preparation of nanofluids. Review the literatures about the nanoparticles used in the refrigeration system and refrigeration oil, and enhance of heat transfer of nanorefrigerant or nanorefrigeration oil. The suspended metallic or nonmetallic nanoparticles change the transport properties and heat transfer characteristics of the host fluid. The aim of this paper is outlook for foreground of the nanoparticles used in the refrigeration system, and to provide a guide line or perspective for future research.