Recent efforts on increasing the multi-functionality of high entropy alloys are receiving significant attention. Though HEA systems are being explored as biomaterials in its bulk form, downsizing them to nanoscale and engineering them for biological applications remains not attempted. Here one-dimensional Fe-Co-Ni-Cu-Zn high entropy alloy nanowires (NWs) are reported as biocompatible nanostructures and primary attempts have been made towards their therapeutic applications. These Fe-Co-Ni-Cu-Zn NWs are a new family of HEAs containing both magnetic and non-magnetic elements, showed good biocompatibility ∼ 80% cell viability and noteworthy photothermal therapy (PTT) mediated cell efficacy that can open new avenues and introduce novel family alloys as bio-HEA nanostructures. © 2022