Prostate cancer is the most commonly diagnosed tumor disease in men, and its treatment is still a big challenge in standard oncology therapy. Magnetically actuated microrobots represent the most promising technology in modern nanomedicine, offering the advantage of wireless guidance, effective cell penetration, and non‐invasive actuation. Here, new biodegradable magnetically actuated zinc/cystine‐based microrobots for in situ treatment of prostate cancer cells are reported. The microrobots are fabricated via metal‐ion‐mediated self‐assembly of the amino acid cystine encapsulating superparamagnetic Fe3O4 nanoparticles (NPs) during the synthesis, which allows their precise manipulation by a rotating magnetic field. Inside the cells, the typical enzymatic reducing environment favors the disassembly of the aminoacidic chemical structure due to the cleavage of cystine disulfide bonds and disruption of non …