OBJECTIVE: To evaluate the efficacy of varicocele repair in patients with nonobstructive azoospermia. STUDY DESIGN: Ten patients with nonobstructive azoospermia and clinical varicoceles who underwent varicocele repair were retrospectively investigated. According to the postoperative appearance of motile spermatozoa in the ejaculate, the patients were divided into 2 groups: Responder and Nonresponder. The outcomes of each group were investigated. RESULTS: There were 4 (40%) patients in the Responder group. Serum follicle-stimulating hormone levels were significantly higher in the Nonresponder group than in the Responder group (19.9±6.4 IU/mL vs. 10.8± 4.0 IU/mL, p<0.05). Mean sperm concentration was 5.4 million spermatozoa/mL in the Responder group. One patient achieved a spontaneous pregnancy, and another achieved an assisted pregnancy. In the Nonresponder group 5 patients underwent microdissection testicular sperm extraction (micro-TESE) postoperatively. In 1 patient, motile spermatozoa were successfully retrieved. Histopathological findings in the other 4 patients were Sertoli-cell-only. CONCLUSION: The present study suggested that varicocele repair could be considered in men with nonobstructive azoospermia who have clinical varicoceles. Moreover, varicocele repair seemed to improve sperm retrieval rate during micro-TESE for those in the Nonresponder group.