The application of drug delivery system (DDS) has achieved breakthroughs in many aspects, especially in the field of tumor treatment. In this work, polyethylene glycol (PEG)-modified hollow mesoporous manganese dioxide (HMnO@PEG) nanoparticles were used to load the anti-tumor drug bleomycin (BLM). When the DDS reached the tumor site, HMnO@PEG was degraded and reduced to Mn by the overexpression of glutathione in the tumor microenvironment, and the drug was released simultaneously. BLM coordinated with Mn , thereby greatly improving the therapeutic activity of BLM. The results of and treatment experiments showed that the DDS had excellent responsive therapeutic activation ability. In addition, Mn exhibited strong paramagnetism and was used for -weighted magnetic resonance imaging . Furthermore, this therapeutic mode of responsively releasing drugs and activating effectively attenuated pulmonary fibrosis initiated by BLM. In short, this DDS could help in avoiding the side effects of drugs.