During standing-up or stepping-on actions, people with lower-limb disabilities must use their arms to sustain their body weight. However, this action will not only increase the wear of the elbow articulations but will also be impossible for the elder or the child to do without other people's assistance. To solve this problem, this article proposes a gravity balance mechanism which can be applied to crutches, armchairs, and other devices to eliminate the influence of body weight. With the help of the proposed mechanism, people with lower-limb disabilities can easily do more daily activities during which they need to overcome their own body weight, such as standing from an armchair. Hence the proposed mechanism can not only promote convenience and quality of life but also increase their self-confidence to rejoin society.