The predefined-time tracking control problem is addressed for Mars entry vehicle under the influence of uncertainties. Firstly, a predefined-time terminal sliding mode surface (PTTSMS) is designed, thus the fast convergence rate is achieved and the corresponding convergence time given by a single parameter can be presented. Then, based on the designed sliding mode surface, a predefined-time terminal sliding mode control (PTTSMC) scheme is devised to ensure that the sliding variable and tracking error are forced into small domains within a prescribed time. Furthermore, by employing the continuous function into control design process, the undesired chattering phenomenon is eliminated gracefully. By virtue of Lyapunov theorem, the stability of closed-loop system in a preset time is proven. Finally, simulation outcomes confirm the efficiency of developed control approach.