Objective：To study the distributions of velocity, wall pressure and wall shear stress of blood flow in the human thoracic aorta under normal physiological pulsatile flow conditions, so as to provide a theoretical foundation for elucidating the pathogenesis of aortic dissection. Methods： By virtue of the Computational Fluid Dynamics and the fundamentals of hemodynamics, the authors obtained the numerical simulations and flow visualizations of pulsating blood flow in the human thoracic aorta. Results： The distributions of velocity, wall pressure, wall shear stress and path line of the blood flow in the thoracic aorta were calculated with a function of time in the cardiac circle. The systoltic wall pressure and its dp/dt were higher than diastolic wall pressure and its dp/dt. The pressure of lateral wall was higher than the pressure of medial wall during systole. A distinct depressed pressure was found located at the intersection between aortic arch and descending aorta. Shear stress of wall of lateral aortic arch was less than that of medial wall of aortic arch and the shear stress change in medial wall of aortic arch was greater than that in the lateral aortic wall. The shear stress was in a cyclic and alternative manner. Conclusion.. The findings suggest that the wall pressure may be related to the development of aortic dissection.