Testicular germ cell tumors (TGCTs) are predominant in young males (15-44 years). Seminomatous and non-seminomatous TGCTs account for about 98% of all TGCTs cases. In this study, we aimed to compare the sperm proteome of patients with seminomatous and non-seminomatous TGCTs to identify possible protein biomarkers that could help distinguish between them in a non-invasive manner.