Under x‐ray irradiation, tumor radiosensitivity was greatly improved by three strategies: (1) tumor hypoxia relief via the catalase‐like activity of Pt NPs, which can convert endogenous H2O2 into O2; (2) direct tumor apoptosis induction via radiosensitizer apoptin; and (3) x‐ray‐induced PDT (X‐PDT) via photosensitizer verteporfin, which can absorb x‐ray irradiation and generate cytotoxic 1O2 for improved PDT efficacy and radiosensitivity. Here, CAT is linked to neoplasm.