Ultrasonography has a great interest in diagnosis of cystic kidney disorders for typical eco-pattern of this pathology. In this work we show the eco-pattern of the most common cystic kidney disorders. Particularly we examine simple cysts (typical, atypical, complicated), multicystic kidney dysplasia, autosomal recessive polycystic kidney disease (infantile) autosomal dominant polycystic kidney disease (adult age). The so-called neoplastic cysts (multiloculated cysts, multiloculated cysts nephroma, cystic nephroblastoma), medullar cysts (medullary sponge kidney, medullary cystic disease), parapyelic cysts, acquired cystic kidney disease in renal failure patients, parasitic cysts, epidermoid cysts. About this disorders we present the more typical and expressive ultrasonographic appearance and we define the role and the opportunity of diagnostic setting by echography, moreover ultrasonography allows us to make a differential diagnosis between cystic kidney disorders and other kidney disease.