A concept of entropy increment ratio ( s ) is introduced for compressible turbulence simulation through a series of direct numerical simulations (DNS). s represents the dissipation rate per unit mechanical energy with the benefit of independence of freestream Mach numbers. Based on this feature, we construct the shielding function f s to describe the boundary layer region and propose an entropy-based detached-eddy simulation method (SDES). This approach follows the spirit of delayed detached-eddy simulation (DDES) proposed by Spalart et al. in 2005, but it exhibits much better behavior after their performances are compared in the following flows, namely, pure attached flow with thick boundary layer (a supersonic flat-plate flow with high Reynolds number), fully separated flow (the supersonic base flow), and separated-reattached flow (the supersonic cavity-ramp flow). The Reynolds-averaged Navier-Stokes (RANS) resolved region is reliably preserved and the modeled stress depletion (MSD) phenomenon which is inherent in DES and DDES is partly alleviated. Moreover, this new hybrid strategy is simple and general, making it applicable to other models related to the boundary layer predictions. Advances in computer speeds have made it possible to utilize more accurate methods of simulating and modeling turbulent flows. However, grid requirements and time cost typically restrict direct numerical simulation (DNS) and even large eddy simulation (LES) to only low Reynolds numbers. That is, Reynolds-averaged Navier-Stokes (RANS) equations along with a turbulence model seem still to be a powerful tool for engineering aerodynamic analysis nowadays, whereas, traditional RANS approaches do not resolve any turbulent flow structures, but model the effect of turbulence on the mean flow in terms of representative mean turbulence scales. As a result, all spectral effects are lost in the time averaging process. The unsteady variant of this, URANS, although managing to resolve non-stationary mean flows, will produce too much eddy viscosity polluting the predicted fields [1,2]. For many turbulent flows of engineering importance, traditional RANS or URANS modeling may be an awkward approach or may fail to reproduce the relevant flow physics. Hybrid RANS/LES approaches [3] represent a credible alternative improving the description of such flows at a reasonable cost by taking into account most of the flow unsteadiness. The main idea of these methods is to model the turbulent structures in the attached region of the flow and to solve the large length-scale structures elsewhere. One of the most popular RANS/LES methods is the detached-eddy simulation proposed by Spalart et al. in 1997 [4] (termed in the following as DES97), which is based on a modification of the length scale employed by Spalart-Allmaras RANS model (SA) [5]. Since the time it was put forward, DES97 has been applied successfully to numerous engineering flow problems, especially in high-Reynolds number separated