Urethral scar is a common urological disease characterized by progressive scarring and fibrosis of the urethral wall, yet its molecular mechanisms remain poorly understood. In this study, we performed DIA-based proteomic profiling using liquid chromatography-tandem mass spectrometry (LC-MS/MS) on human urethral scar tissues (bulbar, n=3; membranous, n=3) and matched normal control tissues (n=6) to characterize the global protein expression changes associated with urethral scar formation.