ABSTRACT Objective Research the importance of gastrointestinal hemorrhage emergency ultrasound pay attention abdominal aortic dissection. Methods Emergency ultrasound examine 2757 cases gastrointestinal hemorrhage patients’ abdominal aortic and larger ramification. Ultrasound discover patients of abdominal aortic intima-media thickening and plaque, distortion, dissection ,widen examined will CT angiography. Ultrasound results contrast with the results of CT angiography. Results Among Patients of discover abnormal abdominal aorta by ultrasound, CT angiography diagnose 12 cases abdominal aortic dissection,ultrasound diagnose 10 cases ,the rest 2 cases after ultrasound find abdominal plaque or widen diagnosed abdominal dissection by CT angiography. Celiac trunk or superior mesenteric artery originate false lumen of abdominal aortic dissection. Conclusion Emergency ultrasound can prompt diagnose abdominal aortic dissection that manifested alimentary tract hemorrhage or provide diagnostic clues. Gastrointestina hemorrhage emergency ultrasound must pay attention abdominal aortic dissection, shouid examine abdominal aortic and larger ramification, avoid misdiagnosis abdominal aortic dissection cause serious consequences .