A comparative study on three theroetical methods for prediction of aerodynamic characteristics of steadu supersonic flow at Mach number form 1.2 to 5.0, over simple thin aerofoil has been conducted. These theories are Shock_Expansion Theory. Ackeret's Theory and Busemann;s Theory. The scope includes the literature study on these various theoretical methods and the basics of the numerical methods in Computational Fluid Dynamics. Then a computer program named SUPER has been developed to obtain the characteristics values using the theoretical methods only, excluding the numerical techniques. This code provided a reasonable accurate predication of the supersonic aerodynamic characteristics across the Mach number range. it can be used in the preliminary design of supersonic aircrafts.