The invention discloses a single-leg jump mechanism based on eccentric non-circular gear drive. With an eccentric non-circular gear transmission way, the device has the characteristic of non-uniform motion; in combination with a better energy storage device, the optimal control potential motion trail is obtained through a non-uniform mechanical transmission way so as to improve the jumping ability; for takeoff, the eccentric non-circular gear drive can provide a better jumping acceleration, the release ability of a calf arc elastic rod can directly act along the jump forwarding direction instead of a way of storing energy by a spring and converting through other ways for output; and for landing, the arc elastic rod on the calf and a calf compression spring can counteract the falling gravity and store the falling potential energy better.