In this paper, computational fluid dynamics simulations were performed on 2-D hypersonic inlets’three-dimensional flow fields by NAPA. The inlets were transform- ed with isolator aspect ratio of 1.0, 3.0, 6.0, and 9.0 in equal windward area and equal windward height. Inner flow character of flow fields were analyzed at design point Mach number 6.0 and some other different Mach number with different back pressure. This investigation would provide some reference for the 2-D hypersonic design and optimi...