Most testicular tumors are germ cell neoplasias. The number of incidentally detected small-sized, nonpalpable testicular lesions is increasing with the use of high-frequency ultrasound for infertility or trauma. These lesions are benign in 80% of cases and can be treated by organ-sparing surgery on the basis of frozen section examination (FSE). We assess the reliability of FSE in testicular and paratesticular lesions and its possible impact on surgical management. We performed a retrospective review of intraoperative FSE in testicular/paratesticular lesions at Geneva University Hospital during a 14-year period. A total of 170 cases were identified, with 159 testicular and 11 paratesticular lesions. The FSE results, permanent sections, and orchiectomy slides were reviewed and compared. Frozen section examinations were reported to be benign in 9 paratesticular and in 43 testicular lesions, and malignant in 2 paratesticular and 105 testicular lesions. Comparing FSE and final diagnosis, FSE correctly identified all nontumor lesions. There was a failure rate of 3.5% to identify tumor. Specificity was 100%, sensitivity was 95%, positive predictive value was 100%, and negative predictive value was 89%. Frozen section examination is a highly sensitive and specific intraoperative procedure, which allows to differentiate between benign and malignant testicular and paratesticular lesions, with a possibility of organ-sparing surgery when they are benign.