The author presents a case of a 16 year old male patient with diffuse back pain. The anamnestics was a surgery performed 10 years ago for phymosis and uretral stricture. The examinations demonstrated bilateral simple renal cysts. The sonographic examinations demonstrated anechoic round mass with a smooth and sharply demarcated wall and through-transmission with strong posterior wall echo in both kidneys. The cysts measured 6-7 cm in diameter and were filled with clear fluid. The CT scan has demonstrated a sharply demarcated cyst with a smooth thin wall, homogenous fluid within the cyst and no contrast enhancement. The clinically most significant task was differentiating it from carcinoma. Treatment options for renal cysts include aspiration, sclerosis, open resection, endoscopic marsupialization and fulguration, percutaneous resection, and laparoscopic resection. This case doesn’t need any treatment only rigorous control.