We design the MnO2/Pt system to enhance the radiosensitization. 1-2 nm of platinum are uniformly dispersed on the as-prepared MnO2 nanosheet. The as-prepared MnO2/Pt are degraded by H2O2 and GSH into magnetic resonance functional imaging materials Mn2+. Moreover, MnO2/Pt can degrade GSH to GSSG, which is obstructed DNA repair of cancer cells after radiotherapy. From the results of colony formation, MnO2/Pt can improve the radiotherapy effect on U87 cells with the treatments of X-ray (8 Gy). MnO2/Pt are expected to achieve integrated magnetic resonance guided sensitization radiotherapy in vivo.