Dissection of the superior mesenteric artery (SMA) not associated aortic dissection is an uncommon event. The pathogenesis remains unclear. Diagnosis has become more efficient due to recent advances in imaging techniques and increased awareness of mesenteric vessel diseases. Early recognition has led to early interventions. Although there is still no consensus on the best option of management for this disease, an increasing number of patients in recent years have been reported to be treated successfully by non-operative approaches (medical therapy and/or percutaneous endovascular repair) rather than operations. We report the diagnosis and non-operative managements of isolated dissection of SMA in the acute stage in two cases at the First Hospital of China Medical University from October to December in 2006.