The invention discloses an assistant rehabilitation robot special for unilateral lower limb disabilities. The assistant rehabilitation robot has three control modes including a passive mode, an active mode and a resistive mode, wherein the assistant rehabilitation robot comprises a waistband component, a thigh lantern ring, a shank lantern ring, a sole component, a thigh component, a shank component, a knee motor device, an ankle motor device, a handle component, a handle connecting rod, a handle motor device, a first leg connecting rod and a second connecting rod; a multi-connecting-rod mechanism serves as a core part and is composed of the handle component, the thigh component, the shank component, the waistband component, the sole component, the first leg connecting rod and the second leg connecting rod which are arranged inside a connecting rod assembly and a fixing assembly. The assistant rehabilitation robot special for the unilateral lower limb disabilities is low in manufacturing cost, light in weight, applicable to exercise and suitable for more people; moreover, the structure of the assistant rehabilitation robot is better in stability and safety, and since the robot is provided with a limiting device, accidents can be effectively prevented from happening.