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Slipping and sinking easily happens on soft terrain, and it will affect the tractive performance of the vehicle. The passing ability on the soft terrain is very important for agricultural terrain-machine and mobile mechanism. Chinese mitten crab is a kind of common arthropod in China, which inhabits the shore of river and lake with mud everywhere. Viewed this way, the capability of going through soft terrain of crab is valuable for designing bionic walking mechanism and agricultural machine, which works on the sand, swamp, beach or wetland. Four bionic walking feet compared with cylinder foot were designed by learning from the Chinese mitten crab dactylopodite. Experiments were separately carried out on dry sand, wet sand, coarse sand and fine sand. Through experimentation the impact of the shape and grooves for foot on in-soil force, bearing force, pullout force and propulsive force were examined. Moreover, the order and contribution rate of every experiment factor on propulsive force were analyzed by orthogonal tests, range analysis and ANOVA. The results showed that the bionic walking foot had superior mechanical characteristics than cylinder foot on sand. In-soil forces of cone shape bionic foot were 64.71%~95.43% smaller than those of cylinder foot. The bearing force of cylinder bionic foot with grooves was 9.48%~24.31% larger than that of cylinder foot. Moisture content was the most critical influence factor on propulsive force. And the propulsive force was increased by about 3.84% with bionic walking foot. For all the bionic walking feet, the pullout forces were smaller, and the maximum reduction reached 89.83%, which indicated that the energy consumption of bionic feet was smaller. The bionic feet could be applied in various walking mechanism for different working conditions. This research provides basis for the design and optimization of soil contact parts for walking mechanism on soft terrain.