Cancer is one of the most serious threats to human health and life. Despite the advances in conventional therapies, such as surgery, chemotherapy, radiotherapy, and immunotherapy, there are still many challenges and limitations in achieving effective and precise cancer treatment. Nanorobots, inspired by natural biological nanomachines, offer a promising alternative for cancer diagnosis and therapy. Nanorobots are nanoscale devices that can perform various tasks under the guidance of external stimuli, such as magnetic fields, light, ultrasound, or chemical gradients. Nanorobots can be designed to target specific cancer cells or tissues, deliver drugs or genes, sense tumor biomarkers, perform minimally invasive surgery, or combine multiple functions for comprehensive treatment. In this chapter, the authors review the recent progress and applications of bio-inspired nanorobots for cancer diagnosis and therapy, with a focus on magnetic field-driven nanorobots. They also discuss the challenges and future perspectives of nanorobots in clinical translation.