Aims: Hydatid cyst disease is a rare cause of upper gastrointestinal bleeding. Peculiarly if it's resulted from a ruptured hepatic artery aneurysm in the hydatid cyst cavity which is fistulated into the duodenum. We here present a case of hepatic artery pseudoaneurysm due to a complicated hydatid cyst with synchronous duodenal fistula. Case: A 45-year-old male was admitted to the emergency department with hematemesis and hematochezia. The patient had a history of a hydatid cyst of liver and a surgical procedure of lung ecinoccosis. Endoscopy revealed an unusual ulcerated lesion in the duodenum. Yellow membranes were observed in the midst and blood oozing. After unsuccessful endoscopic sclerotherapy, a Computerized Tomography (CT) was performed. CT revealed a ruptured hydatid cyst into the duodenum and bleeding from the formed hepatic artery pseudoaneurysm. Hepatic artery coil embolization was performed urgently and a percutaneous transhepatic drainage catheter was applied to maintain the bile flow. Subsequently, a 10 Fr , 10 cm plastic stent was inserted via Endoscopic Retrograde Cholangiopancreatography (ERCP). The rare complication which was observed after embolization was the hepatic abscess. Although a percutaneous catheter was inserted initially, drainage wasn’t successful. As a last option, surgical debridement was considered. Conclusion: If a patient who presented with upper gastrointestinal bleeding with a previous history of liver hydatid cyst, cyst complications must be listed as a differential diagnosis. Besides endoscopy, contrast-enhanced CT and ЕRCP are the essential diagnostic and therapeutic approaches.