Background: Green synthesis techniques have drawn a lot of interest lately since they are beneficial to the environment and have potential uses in a variety of industries, including biomedicine. Because of their special physicochemical characteristics, copper nanoparticles (CuNPs) have become one of the most interesting options for use in biological applications among nanomaterials. An overview of green synthesis methods for CuNPs is given in this review, along with a discussion of their applications in cancer therapeutics. The benefits and drawbacks of certain green synthesis techniques, such as plant-mediated, microorganism-mediated, and other environmentally friendly processes, are discussed. Moreover, a thorough discussion is given of CuNPs’ biological uses, including their antibacterial activity, anticancer potential, drug transport, and bioimaging capabilities. Furthermore, difficulties and prospects for the application of green-synthesised CuNPs in biomedicine are discussed. © 2024 Elsevier B.V., All rights reserved.