Nanofluids are widely used in recent years in order to enhance heat transfer in several mediums. Thermal perfor-mance of thermosyphons can be improved by employment of nanofluids. In this study, a comprehensive reviewis conducted on the studies focused on the thermosyphonsfilled with nanofluids. In addition, thermosyphonsworking with nanofluids in various applications are reviewed here. Based on the literature review, nanofluidshave potential to significantly improve thermal performance of thermosyphons. In addition, it is concludedthat thermal performance of nanofluidic thermosyphons depends on type of nanoparticles, basefluid, concentra-tion and etc. Most of the reviewed studies have found that there is an optimum concentration for the nanofluidsused in thermosyphons. In addition, the efficiency of the devices use nanofluidic thermosyphons are improveddue to increased effective thermal conductivity of thermosyphons charged with nanofluids