INTRODUCTION: Splenic artery pseudoaneurysm (SAPA) is a potentially fatal but rare complication of acute or chronic pancreatitis. We present a case of 37-year-old male with history of pancreatitis and a 7.9 cm pseudocyst complicated by hematemesis requiring coiling embolization and massive reperfusion. CASE DESCRIPTION/METHODS: A 37-year-old male with history of chronic pancreatitis complicated by pancreatic pseudocyst measuring 7.9 cm presented with acute left upper quadrant abdominal pain and new hematemesis. He appeared diaphoretic, pulse 125 bpm, blood pressure 141/72 mmHg; with no palpable abdominal mass or bruits. Initial labs revealed hemoglobin of 12.8 gm/dL, lipase 74,238 units/L and lactic acid 4.9 mmol/L. Patient underwent CT abdomen/pelvis that revealed acute hemorrhage into the stomach with multiple wedge-shaped splenic hypodensities suggestive of infarcts. Patient continued to rapidly decompensate progressing into hemorrhagic shock requiring massive blood transfusion and vasopressors. Emergent EGD showed plethora of blood with clots in the gastric body with no visible source of bleeding. Due to limitations of endoscopy, patient was taken emergently for mesenteric angiography. A large SAPA with active extravasation into the stomach was visualized and successfully embolized using coiling technique. Total of 30 units of RBCs, 9 units platelets, 15 units plasma and 8 units cryoprecipitate were transfused. Patient recovered well post-op requiring no further transfusions and discharged home in stable condition. DISCUSSION: Due to diagnostic challenges and varied initial presentations, splenic artery pseudoaneurysm (SAPA) is a rare disorder predominantly associated with acute/chronic pancreatitis, pancreatic pseudocyst, or trauma. Mostly commonly, the splenic artery is affected in true visceral aneurysms versus the hepatic artery in visceral pseudoaneurysms. SAPAs have a high risk of rupture with a three-fold higher incidence in men, and a mortality rate of up to 90% if untreated. While computed tomography is often the first diagnostic test, mesenteric angiography is the gold standard. Treatment options vary from endoscopic ultrasound guided coiling, percutaneous coiling/stent, or surgical repair. This case emphasizes the need of early recognition, massive reperfusion, and definitive treatment before rapid decline from hemorrhagic shock. Sudden epigastric pain with hematemesis in patients with chronic pancreatitis or pancreatic pseudocysts, may be clues in the development of this rare complication.