The invention discloses an exoskeleton rehabilitation robot for rehabilitation of a lower limb walking function and a control system and method thereof. The robot comprises a backrest, a hip joint power source, a hip joint component, a waist component, a thigh bar component, a knee joint power source, a knee joint component, a shank bar component, an ankle joint component and a foot pedal. According to the lower limb exoskeleton rehabilitation robot, a driving scheme is designed by utilizing a bionics principle, so that the initiative degree of freedom of the ankle joint is increased; through initiatively pulling the heel tendon muscles of the patients, the rehabilitation speed of the ankle joint function is improved; the waist component, a connection rod mechanism and the foot pedal adopt a carbon fiber composite material, so that the structure weights and volumes are lightened while the strength is kept; and a non-polar adjustable function is set for the waist width, thigh length and shank length, and flexible bandages are equipped, so that the wearing comfort level requirement of the users is satisfied to the greatest extent. The robot disclosed by the invention not only can be used as a tool for riding instead of walk for the patients with walking disability, but also can help the stroke patients to obtain walking ability again through initiative training.