Antitumor therapies based on reactive oxygen species (including photodynamic, sonodynamic and chemodynamic therapy) have attracted extensive attentions in recent years. Among them, chemodynamic therapy requires no external energy (light or ultrasound) and oxygen, but mainly relies on the Fenton or Fentonlike reaction between metal catalysts (Fe2+, Cu+, etc) and hydrogen peroxide molecules to produce highly oxidizing active species (like cytotoxic hydroxyl radical ·OH). These active species destroy biological macromolecules (such as cell lipids, proteins and DNA, etc.), and trigger cell apoptosis, thus achieving tumor therapy. Compared with traditional chemodynamic therapy nanomaterials (Fe3O4, Cu2O, etc.), metal peroxides-based materials have gradually gained people’s attention, and show great potentials for chemodynamic therapy application due to their low pH-responsive degradation and self-providing H2O2 features. Metal peroxides materials can generate H2O2 and metal ions under slightly acidic tumor microenvironment, and kill tumor cells by increasing H2O2 level and overloading intratumoral metal ions, or by further producing ·OH via Fenton or Fenton-like reaction between metal ions and H2O2. In addition, some metal ions can inhibit mitochondrial electron transport chain to synergistically kill tumor cells, thus improving multimodal therapeutic effect on tumors. In this paper, the concept and treatment mechanism of chemodynamic therapy are first introduced, and the reaction principle and mechanism for several different kinds of metal peroxides nanomaterials are summarized. Then the recent domestic and foreign research progress of pH-responsive/H2O2 self-supplying metal peroxides nanomaterials applied for tumor treatments is reviewed.Finally, their application potentials, development trends and possible challenges are prospected.