Although testicular cancer (TCa) is rare neoplasm that occurs in young men aged between 18 and 35 years. The risk factors are cryptorchidism, family history, and infertility. The aim of this study was to investigate the diagnostic efficacy of neutrophil to lymphocyte ratio for the diagnosis of TCa. The patients who underwent orchiectomy in our unit reviewed retrospectively. Age of the patients, the laboratory results and pathological reports were recorded. The neutrophil to lymphocyte ratio (NLR) was calculated as the neutrophil counts divided to the lymphocyte counts. The patients were divided into two groups according to the pathology record. The testicular malign neoplasms are included in group 1 and group 2 includes the patients who had cryptorchidism and atrophic testes without any malignancy and inflammation. For statistical analysis, student t test was used for comparing the data between groups and the area under curves were used for NLR, neutrophil and lymphocyte counts in the diagnosis of testicular malign neoplasms.There were 285 patients in the present study. The patients' age was between 10 and 90 with a mean age of 36.87 ± 11.83 and 37.24 ± 20.31 years in groups respectively.The neutrophil, white blood cell counts and NLR were significantly higher in group 1 and lymphocye count was lower in patients with testicular cancer with statistical significance. The area under curve was 0.645, 0.626, 0.578 for NLR, neutrophil and lymphocyte counts for the diagnosis of TCa. Mixed germ cell tumor was the most common histologic subtype with an incidence of 51.58%(n:65 patients) and seminomas were reported 37.30% (n:47 patients) of the patients. Testicular cancer has low incidence when compared the other urologic malignancies. There are only three tumor markers that include alpha-fetaprotein, human chorionic gonadotropin and lactate dehydrogenase for testicular cancer diagnosis. The current study showed Neutrophil to lymphocyte ratio (NLR) may be used as a biomarker for TCa. Further studies are needed to define the assocaiton between NLR and testicular cancer.