Objective To explore a simple and rapid evaluation method for successfully establishing a mouse model of thoracic aortic aneurysm/ dissection. Methods Twenty-four 3-year-old C57BL/6 male mice were randomly divided into either the model or control group. The model mice were fed a normal diet and given drinking water containing β-aminopropionitrile for 4 weeks. The control mice were fed a normal diet and given normal drinking water. The body weights of the mice were dynamically monitored, and the thoracic aorta and left common carotid artery were detected using the Vevo 2100 small animal ultrasound system at week 4 of the experiment. The thoracic aorta was observed by microcomputed tomography. Results The body weights of the model group were significantly decreased at week 4 compared with those of the control group. Ultrasound and micro-computed tomography revealed that the thoracic aortas of the model group were significantly enlarged with the aortic aneurysm formation; the pulse wave velocity changed, and the arterial stiffness increased significantly. Conclusions Ultrasound imaging can be used to easily, quickly and safely evaluate the success in establishment of the mouse model of thoracic aortic aneurysm/ dissection and dynamically monitor the changes in aortic aneurysm size and arterial stiffness.