Cystic echinococcosis, caused by Echinococcus granulosus eggs, is a parasitic zoonosis that typically affects humans through accidental ingestion. Polycystic liver disease is a condition characterized by the presence of multiple liver cysts and is often associated with polycystic kidney disease. Here, we present a case of a man in his 70s with a pre-existing diagnosis of polycystic liver disease. Radiological findings of a suspicious cyst in the S4 segment initially lacked serological evidence of echinococcosis; however, intraoperative confirmation revealed the presence of an echinococcal cyst. This article aims to explore both clinical conditions and highlight the therapeutic considerations for their management. Moreover, we discuss the significance of this unique case, emphasizing the possibility of the coexistence of these two pathologies.