Parallel computation of flow fields around a space-plane has been conducted on the Numerical Wind Tunnel (NWT) at the National Aerospace Laboratory, aiming to apply the compressible Navier-Stokes code which super/transonic flows with to solve low subsonic flow have been simulated fields. Computational results show its sufficient reliability in terms of predicting aerodynamic forces. Thus, a prospect to make the present code a robust flow solver covering from a low subsonic to a supersonic regime with modifications has been obtained. To realize it, further more effort is needed to get convergence efficiency of computation and to analyze the mechanism of microscopic flow phenomena.