Abstract: The supersonic inviscid contour design methods were studied for the hypersonic wind tunnel axial-symmetric nozzle. The Direct-design technique based on the axial Mach number distribution presetting was introduced, the axial Mach number distribution presetting method based on the ratio of area was improved, and a new multipoint-control characteristic point distribution method was proposed. The designed nozzle characteristic network was triangulated and compared with the numerical simulation result, and influencing factors were analyzed for the nozzle inviscid contour. Results indicate that: the feasibility of the axial Mach number distribution presetting method based on the ratio of area is guaranteed by the present improvement; the nozzle inviscid contour is significantly affected by the axial Mach number distribution, axial characteristic point distribution and the amount of characteristic points on the boundary.