Abstract: As the first modeling flight test in China aiming at fundamental hypersonic aerodynamics problems, the real flight of MF-1 is absolutely successful, but there are also some differences between designed trajectory and real uncontrolled flight trajectory. In this paper, the cause of trajectory bias between flight test and preflight design is studied by theoretical analysis and flight simulations firstly. Results show that, wind distribution measurement errors and predicted aerodynamic errors should be the main reasons for that trajectory bias. Then, the flight trajectory of the MF-1 is reconstructed using flight overload and angular rate data, and the whole flight trajectory data including angle of attack and angle of slide are obtained. It is also shown that, the wind measurement has significant effects to the accurate estimation of angle of attack and angle of slide if there is no direct measure of flow angle.