Hitchhiking is a phenomenon of cruising on surfaces. Inspired by this process, biomimetic delivery systems leveraging the intrinsic ability of circulatory cells to target tumors exhibit considerable potential in cancer theranostics. Besides human circulatory cell-mediated hitchhiking, bacteria-driven hitchhiking strategies also manifest promise in cancer therapy. Such tactics are primarily built using nonpathogenic invasive bacteria with tumor homing capabilities. The chemotherapeutic cargos are hitchhiked onto the circulatory cells or bacterial spores for tumor-targeted delivery. By integrating the benefits of such cells and therapeutic cargo, numerous efficient delivery systems that implement the notion of hitchhiking for cancer therapy are generated. Following an overview of several hitchhiking concepts, this article reviews various cellular and bacterial hitchhiking approaches for cancer treatment. Additionally, the challenges and prospects in the field of cancer theranostics related to hitchhiking are also discussed. © 2022 Wiley-VCH GmbH.