Abstract: Terramechanics concerns studies on the interaction between vehicles andrough terrain in off-road locomotion. The main topics include predictionof vehicle mobility performance, optimum design of mobility systems and soiltrafficability evaluation. In this paper, the methodology, testequipment and main results of terramechanics are reviewed, and the recentprogress is discussed. The paper focuses on the applications ofterramechanics theory in planetary exploration, including the design, validation of planetary rover,development and characterization of simulated soil and in situ mechanical parameter measurement of planetary soil. The possible future directions of this field are also discussed.