Lipid　peroxidation　(LPO)　is　one　of　the　most　damaging　processes　in　chemodynamic　therapy　(CDT).　Although　it　is　well　known　that　polyunsaturated　fatty　acids　(PUFAs)　are　much　more　susceptible　than　saturated　or　monounsaturated　ones　to　LPO,　there　is　no　study　exploring　the　effect　of　cell　membrane　unsaturation　degree　on　CDT.　Here,　we　report　a　self-reinforcing　CDT　agent　(denoted　as　OA@Fe-SAC@EM　NPs),　consisting　of　oleanolic　acid　(OA)-loaded　iron　single-atom　catalyst　(Fe-SAC)-embedded　hollow　carbon　nanospheres　encapsulated　by　an　erythrocyte　membrane　(EM),　which　promotes　LPO　to　improve　chemodynamic　efficacy　via　modulating　the　degree　of　membrane　unsaturation.　Upon　uptake　of　OA@Fe-SAC@EM　NPs　by　cancer　cells,　Fe-SAC-catalyzed　conversion　of　endogenous　hydrogen　peroxide　into　hydroxyl　radicals,　in　addition　to　initiating　the　chemodynamic　therapeutic　process,　causes　the　dissociation　of　the　EM　shell　and　the　ensuing　release　of　OA　that　can　enrich　cellular　membranes　with　PUFAs,　enabling　LPO　amplification-enhanced　CDT.