This paper presents flight control designs of an unmanned space vehicle, HOPE-X, vehicle using interpolation gain scheduling techniques. There are three flight phases from deorbit to landing in HOPE-X; reentry, terminal area energy management (TAEM), and approach and landing. This paper is addressed to the TAEM phase in which an amount of lateral maneuvers are required. Two interpolation gain scheduled state feedback laws were designed with respect to the Lyapunov functions used for guaranteeing the global stability of the closed-loop system, and were applied to the numerical simulations of the HOPE-X. As a result, the gain scheduled control law showed better control performance in the entire of TAEM phase than fixed state feedback laws. The gain scheduling using a parameter-dependent Lyapunov function was superior to the one using a conventional Lyapunov function.