Aiming at the cruise segment trajectory prediction problem of near space reentry gliding vehicle, a trajectory prediction algorithm based on control law prediction was proposed. By analyzing and deriving the unknowns in the trajectory prediction and studying the flight modes and control laws of the cruising segment, the feasibility of trajectory prediction was clarified. The discriminating methods of two kinds of flight trajectories are studied: balanced gliding and jumping gliding. On this basis, a trajectory prediction algorithm based on control law prediction was designed. The algorithm was verified by simulation. The influence of tracking time and tracking starting point on trajectory prediction accuracy was studied. The results showed that the algorithm had high accuracy for different types of trajectories; the tracking time had a great influence on trajectory prediction accuracy; but the impact of tracking start point was small.