The supersonic variable Mach number wind tunnel can operate at multiple Mach numbers during a single operation, which has unique advantages for studying supersonic maneuvering process and scramjet Ramjet starting. The supersonic variable Mach number nozzle is the core component for adjusting Mach number during wind tunnel operation, and its design quality directly determines the flow field quality of the experimental section. This article reviews the research progress of nozzle design in supersonic variable Mach number wind tunnels both domestically and internationally in recent years, and introduces four typical variable Mach number wind tunnel nozzle schemes (flexible wall, semi-flexible wall, profile rotation, asymmetric), as well as their numerical simulation and experimental calibration results; Summarized the key considerations in the design of different variable Mach number nozzle schemes, and provided prospects for the next research direction.