Abstract. Several important characteristics of shock wave/boundary layer interaction (SBLI) produce significant challenges to accurately simulate this problem. This work presents the numerical study of shock wave/boundary layer interaction utilizing two high-resolution numerical methods – total variation diminishing (TVD) and weighted essentially non-oscillating (WENO). Both techniques are investigated and compared in relation to flow over a backward-facing step application, which involves a combination of complex flow structures downstream of the step. The WENO method used in this study is the modified third-order version which minimizes the inherent dissipation of the fifth-order classical WENO. A consistent and conservative monotone flux method is employed to discretize the spatial derivatives and the numerical flux at the cell interface in each coordinate direction is achieved by one dimensional WENO reconstruction while keeping the variation in other directions of coordinate system fixed. The time integration is performed by the optimal third-order TVD Runge-Kutta scheme. The results obtained from the improved version of the WENO method give enhanced resolution of discontinuities (shock and rarefaction) and vortices compared with those obtained from the second-order TVD method. Moreover, the pressure distribution obtained from the modified WENO method agrees well with the experimental results.