PURPOSE: Testicular microlithiasis (TM) is an uncommon benign condition characterized by calcium deposits in the lumen of the seminiferous tubules. It may be associated with testicular malignancies and infertility. MATERIALS AND METHODS: We performed a retrospective review of clinical charts and scrotal ultrasound findings of 18 patients who were found to have TM. Scrotal ultrasound scans were performed using 5- to 10-mHz high-resolution transducers. The indication for ultrasonography was an abnormal scrotal examination. RESULTS: The mean age at presentation was 39.9 years (range 14 to 70 years). Most (15; 83.3%) of the patients had bilateral TM. There were no differences in the sonographic patterns and appearance according to patient age. A third of the patients (7; 38.9%) had benign epididymal lesions. Two with bilateral TM had unilateral testicular malignancy. A varicocele was identified in two men, who demonstrated normal semen parameters. A 16-year-old boy showed no interval sonographic changes at 1-year follow-up. CONCLUSIONS: Testicular microlithiasis usually affects both testes. The association between TM and progres sion of cancer is unclear.