Ultrasonic investigations (USI) were used in the diagnosis of closed renal injuries in 59 patients (51 males and 8 females) aged from 17 to 65 years. The lesion of the right kidney was diagnosed in 35 (59.3 per cent) patients, the left kidney was affected in 24 (40.7 per cent) of examinees. In 2 persons the injury of the kidney was combined with the lesion of the urinary bladder. According to USI results, the patients with suspected closed trauma were enrolled in 4 groups: persons with an intact renal parenchyma, fibrous capsula and pelvicaliceal renal system (the contusion of the kidney); persons with normal ultrasonic picture of the kidney and the presence of intermuscular hematoma; those with subcapsular hepatoma; and those with pararenal hematoma. USI technique turned to be high-informative in the diagnosis of the occult renal injuries and permitted evaluating the structure of the kidney, the character and degree of the lesion and following up the status of the compromised organ during the conservative treatment.