Abstract: A method is proposed for the design of an elliptical nozzle.The flow fields of the elliptical nozzle and the rectangle one are analyzed and compared.The numerical simulations indi-cate that the exit Mach number of the elliptical nozzle is greater than that of the rectangle one un-der the same conditions,i.e.the same reservoir parameters,length and exit area.The turbu-lence and high temperature real gas effects reduce the effective area ratio and change the expan-sion waves.A fine uniform outflow can be obtained by choosing an appropriate location of the ex-it.As a special device for the hypersonic wind tunnel experiments,the elliptical nozzle can im-prove the simulation ability of the wind tunnel by its high efficiency in using the energy of the heater.This nozzle can be applied to perform the thermal protection experimental researches on large-scale models with flat-like leading edge,helm or wing and on large length-width ratio scramjet engines.