According to the technical measures for reducing the mechanical soil compaction, all terrain adaptive locomotion chassis for farmland with ultra-low pressure tires was proposed as solution scheme based on the conventional wheeled locomotion mechanism. The mechanical model between the tire and ultra-low pressure was established. The terramechanics of all terrain adaptive locomotion chassis for farmland which used ultra-low pressure tires was anayled. At last, compared with the existing four-wheel drive tractor, it was proved that all terrain adaptive locomotion vehicles for farmland could reduce the mechanical soil compaction and met the modern agriculture’s need with well performance and tractive effort.