Platinum-drug-based chemotherapy in clinics has achieved great success in clinical malignancy therapy. However, unpredictable off-target toxicity and the resulting severe side effects in the treatment are still unsolved problems. Although metabolic glycan labeling-mediated tumor-targeted therapy has been widely reported, less selective metabolic labeling in vivo limited its wide application. Herein, a novel probe of B-Ac3ManNAz that is regulated by reactive oxygen species in tumor cells is introduced to enhance the recognition and cytotoxicity of DBCO-modified oxaliplatin(IV) via bioorthogonal chemistry. B-Ac3ManNAz was synthesized from Ac4ManNAz by incorporation with 4-(hydroxymethyl) benzeneboronic acid pinacol ester (HBAPE) at the anomeric position, which is confirmed to be regulated by ROS and could robustly label glycans on the cell surface. Moreover, N3-treated tumor cells could enhance the tumor accumulation of DBCO-modified oxaliplatin(IV) via click chemistry meanwhile reduce the off-target distribution in normal tissue. Our strategy provides an effective metabolic precursor for tumor-specific labeling and targeted cancer therapies.