The invention discloses a seated horizontal type lower limb rehabilitation robot and a corresponding passive training control method. The robot comprises a chair, mechanical arms, a man-machine interaction interface and a main industrial control box. When the rehabilitation robot is utilized to assist a patient in participating in passive training, the patient reclines on the chair; the lower limbs on two sides of the patient are respectively fixed with the mechanical arms; a speed instruction signal and a position instruction signal are generated by a host computer in the main industrial control box according to a motion track preset by a user, present positions of the mechanical arms and an expected motion track; the corresponding motion control card, joint driver and motor/encoder are utilized to control the mechanical arms to drive the lower limbs on two sides of the patient to participate in the rehabilitation training; and the traditional occupational therapy and motion therapy are organically combined according to the invention, so that the rehabilitation effect of the patient is effectively improved.