The invention relates to a foot module (7) for an exoskeleton structure, comprising an ankle joint (72), a first support plate (732) designed to be supported on the top of a boot of the user, when the foot module (7) is attached to the foot of the user, a second support plate (735) capable of being disposed under the sole of the boot, a first segment (731) connecting the ankle joint (72) to the first support plate (732) and a second segment (733) connecting the first support plate (732) to the second support plate (735), the first segment (733) and the second segment (735) forming a spring capable of being compressed when the boot is in contact with the ground (S) and being expanded when the boot is not in contact with the ground (S).