Abstract: New demands on ground tests were made because of the rapid development of novel hypersonic flight vehicles. However, these requirements can be hardly satisfied for the moment. In the present study, the general similarity rules of aerodynamic research in ground wind tunnels were reviewed. Then the shortcomings and challenges of ground test simulations of state-of-the-art aerodynamics, aerothermodynamics and propulsion were analyzed. It is concluded that the current critical parameter simulation, assembly simulation and local similarity simulation are still valid, whereas the ground test should be guided by similarity theory and supported by numerical calculation more intensively. Moreover, flight test should be conducted if necessary to validate and verify the results obtained with incomplete similarity simulation.