INTRODUCTION AND IMPORTANCE: Splanchnic venous thrombosis is a rare but serious complication of bariatric surgery. This case report highlights a unique occurrence of acute portal, mesenteric, and splenic vein thrombosis in a 39-year-old woman three weeks after undergoing laparoscopic sleeve gastrectomy for severe obesity. CASE PRESENTATION: A 39-year-old woman with a BMI of 38.1 kg/m CLINICAL DISCUSSION: Diagnosing SVT is difficult due to its non-specific symptoms, relying on advanced imaging techniques like Doppler ultrasound, CT, or MRI. Anticoagulation therapy, such as low-molecular-weight heparin (LMWH) followed by direct oral anticoagulants (DOACs), is essential for managing SVT. Supportive treatments, including PPIs and antibiotics, improve outcomes, and surgery may be necessary for complicated cases like end organ damage for instance intestinal ischemia and necrosis. CONCLUSION: This case underscores the need for high clinical suspicion of splanchnic venous thrombosis in post-bariatric surgery patients presenting with persistent abdominal pain. Proper patient selection and stratification, adequate thromboprophylaxis are crucial preventive strategies. Early diagnosis and aggressive management with multidisciplinary team approach are critical to preventing severe complications and improving outcomes.