Abstract: BACKGROUND: Walking is the most basic movement mode of the human, exploring the stress characteristics of the foot and the difference between the feet during walking is of great value to deeply understand the law of human walking. 
OBJECTIVE: To explore the foot function and walking law of human body in each stage of gait support through the processing and analysis of foot balance curve. 
METHODS: 116 subjects with normal foot type were selected by foot type and walked at their own optimal speed to record their plantar pressure data. A foot balance curve was drawn with average value and 1 times standard deviation. The curve rules and eigenvalues of dominant and non-dominant lateral feet were analyzed. 
RESULTS AND CONCLUSION: (1) During the walking support period, the force characteristics of the foot on the horizontal side constantly changed. From initial contact phase to forefoot contact phase, the foot stabilized its posture through the force migration. (2) In foot flat phase, the plantar force shifted to the outside. In forefoot push off phase, the plantar force shifted from outside to inside and the human body balanced through bipedal support. (3) There was no significant difference in the relative duration of initial contact phase, forefoot contact phase, foot flat phase, and forefoot push off phase between the dominant foot and the non-dominant foot (P > 0.05). (4) The characteristic similarity of the bilateral foot balance curve was highly consistent and the foot balance curve of the dominant side was lower than that of the non-dominant side (P < 0.05). (5) It is concluded that the changes of foot posture and foot function during human walking are reflected by the foot balance curve. The function of human feet is the same at all stages of the gait cycle, and the force acting on the dominant side is more lateral than that of the non-dominant side, and the pedal and extension function is more fully performed on the horizontal axis. The foot balance curve has an important reference value for the study of human walking law and the evaluation of foot function. 

Key words: plantar pressure, foot function, foot balance curve, gait, biomechanics