Oxidative stress triggers redox-sensitive post-translational modifications, notably disulfide bond formation involving cysteine residues. However, these bonds are often overlooked in proteomics due to the routine use of reducing agents. Here, we employed liquid chromatography–mass spectrometry (LC-MS) based metabolomics and non-reducing tandem mass tag (TMT) proteomics to investigate the effects of H₂O₂ on MDA-MB-231 cells. Metabolomic analysis revealed pathway-specific inhibition of major metabolic pathways including glycolysis, the tricarboxylic acid (TCA) cycle, and nucleotide biosynthesis. Proteomic analysis using the DBond algorithm revealed extensive and isoform-specific disulfide crosslinks across more than 1,000 proteins. These linkages were enriched at redox-sensitive cysteines near basic residues and displayed high isoform specificity. Our findings demonstrate that disulfide bond formation serves as a selective mechanism of redox regulation. This study highlights the utility of non-reducing proteomics in elucidating redox-controlled protein networks and structural dynamics under oxidative stress.