貯精囊腫同時合併有同側腎發育不全或無發育的情況並不多見，臨床表現為多樣性，可能是無症狀或出現排便、排尿的困難，其診斷並不是很難，而是端賴於醫師本身是否察覺到病變的存在，我們提出兩病例的經驗並參閱文獻，說明胚胎異常之因，並探討鑑別診斷及治療方式。

Cyst of seminal vesicle associated with ipsilateral renal agenesis is rare. The clinical mani-festation may be asymptomatic or present with voiding or defection problems. Herein, we re-port two cases of seminal vesicle cyst with ipsilateral renal agenesis. The embryological ex-planation of this abnormality is reviewed and the differential and management dis-cussed. (J Urol R.O.C., 9:204-207,1998)