Abstract: The Free-flight test launch technology is one of the key technologies in the free-flight test. Hypervelocity Aerodynamics Institute, CARDC, researched and developed the model launch device for the conventional hypersonic wind tunnel, and conducted a series of free-flight tests in the hypersonic wind tunnel with Mach number being 6. The free-flight test results indicate that: the launch device worked well, and the attitude of the model is stable. According to the different wind tunnel specific circumstances, the size of the launch device can be reformed, which can be applied to different hypersonic wind tunnels. Launch pressure and launch velocity are important parameters, which should be considered at the structure design stages. The model fixed component also needs the adaptability design according to the different model shapes.