Objective To study the application of 16-slice spiral CT imaging in diagnosis of aortic dissection.Methods Sixty-one patients with aortic dissection were examined through 16-slice spiral CT imaging.Post-processing techniques were MPR,MIP and VR.Results According to AD,type Ⅰ were 10 cases,type Ⅱ 8 cases and type Ⅲ 43 cases.After contrast-enhanced scanning,true and false lumen and intimal flap of aortic dissection could be shown in all of 61 cases.32 patients have re-entrance,in which 1 patients had five re-entrances,2 patients three re-entrances and three patients haven't any re-entrance.61 patients had explicited true and false lumen.16 patients had intimal calcification and 28 patients had mural thrombus.Conclusion Angiography with 16-slice spiral CT in the diagnosis and evaluation of aortic dissection is a more effective non-invasive screening method with some essential value for the clinical therapies.