ALB and lip and oral cavity carcinoma: This structure not only enhances the stability of the formulation but also improves drug delivery to tumors through the endogenous natural albumin pathway.[12] Inspired by the structure of a canonical nanodrug Abraxane, herein, as proof of concept, we describe a human serum albumin (HSA)‐modified CaO2 nanoparticles (CaO2‐HSA) system (Scheme 1), and explore its application as the radiosensitizer toward in situ oral cancer.