Inflammation in bone defect after being implanted scaffold is related to oxidative stress, which is caused mainly by higher concentration of hydrogen peroxide (H₂O₂). Manganese dioxide (MnO₂) can catalyze H₂O₂ decomposition to decrease excessive H₂O₂ in the surrounding environment of scaffolds. Furthermore, the oxygen (O₂) generated by the decomposition of H₂O₂ can alleviate the hypoxia caused by insufficient blood supply in bone defects, which is conducive to bone tissue regeneration. Here, a simple redox method was proposed to deposit MnO₂ particles on the surface of 3D printed bioactive glass (BG) scaffolds for the preparation of BG-MnO₂ composite scaffolds (BGM), which endows BG-MnO₂ scaffolds with the ability of H₂O₂ scavenging and O₂ supplying simultaneously. The results showed that the MnO₂ content deposited on the surface of BGM scaffolds was increased with the increase of potassium permanganate concentration in the reaction solution, and the compressive strength of BGM scaffolds was increased with the increase of MnO₂ content. However, porosity and degradation rate of these scaffolds with or without MnO₂ remained the same. More importantly, BGM scaffolds can continuously catalyze the decomposition of H₂O₂ to produce O₂ in H₂O₂ environment. When BGM with different Mn content scaffolds (BMG5 and BGM9) catalyzed the decomposition of H₂O₂ to produce O₂ in 2 mmol/L H₂O₂ solution, the saturated oxygen concentration in the solution could reach 8.4 and 11 mg/L, respectively. In vitro cell experiments showed that BGM scaffolds could promote the proliferation and alkaline phosphatase activity of rabbit bone marrow mesenchymal stem cells. Hence, BGM scaffolds show great potential in bone regeneration.