Fenton catalytic medicine that catalyzes the production of center dot OH without external energy input or oxygen as a substrate has reshaped the landscape of conventional cancer therapy in recent decades, yet potential biosafety concerns caused by non-safety-approved components restrict their clinical translation from the bench to the bedside. Herein, to overcome this dilemma, we elaborately utilizate safety-approved hetastarch, which has been extensively employed in the clinic as a plasma substitute, as a stabilizer participating in the copper chloride-initiated polymerization of pyrrole monomer before loading it with DOX. The constructed DOX-loaded hetastarch-doped Cu-based polypyrrole (HES@CuP-D) catalyzes the excess H2O2 in tumor cells to center dot OH through a Cu+-mediated Fenton-like reaction, which not only causes oxidative damage to tumor cells but also leads to the structural collapse and DOX release. Additionally, HES@CuP-D together with laser irradiation reinforces tumor killing efficiency by hyperthermia-enhanced catalytic activity and -accelerated drug release. As a result, the developed HES@CuP-D provides a promising strategy for Fenton catalytic therapy with negligible toxicity to the body. Biodegradable HES@CuP-D with good dispersibility has been elaborately fabricated by one-step synthesis using safety-approved hetastarch as a novel stabilizer and CuCl2 as an oxidant for hyperthermia-accelerated DOX release and -enhanced Fenton catalysis against malignant tumors.