Clinical differentiation of the various pathological conditing scrotal contents can be difficult. The superficial location of scrotum is suited for sonographic examination. March, 1984 to December, 1987 authors experienced 23 cases of the inflammatory and tumorous conditions, which were confirmed by operation and clinical follow up. The results are as follows: 1.Sonographic examination is safe, nonivasive, and useful in screening test of scrotum. 2.Sonography is useful for the confirmation of complicated epididymitis. 3.In palpable mass cases, sonogaphy can differentiate intratesticular and extratesticular lsions. 4.Sonography is useful for detection of primary tumor in clinically uncertain conditions. 5.In epididymitis, sonography shows enlargment and decreased echogenecity of epididymis, reactive hydrocele, and thickening of scrotal wall. 6. In testicular tumor: seminoma shows hypoechoic solic mass lesion with enlargement. Embryonal cell carcinoma shows ill defined hypoechoic testicular enlargment. Rhabdomyosarcoma shows ill defind hypoechoic mass with central necrosis. Metastatic testicular tumor shows bilaterality and ill defined abnormal echogenecity, more older age distribution.