The invention discloses a sitting and lying type lower limb rehabilitation robot, which can respectively carry out a passive training, an assisted training or an active training according to the damage degree or the rehabilitation stage of a patient. The robot comprises a seat, a mechanical arm, a main industrial control box, a man-machine interaction interface, an electrical stimulation handheld switch, an electrical stimulation electrode plate, an electromyographic signal acquisition electrode plate, a functional electrical stimulation instrument and an electromyographic signal acquisition industrial control box. During the passive training, the lower limb of the patient is trained according to a set movement locus; during the assisted training, the main muscle group of the lower limb of the patient is applied with electrical stimulation pulse; according to the movement locus of a tail end, the electrical stimulation pulse is subjected to sequential control to finish the assisted training; during the active training, the electromyographic signal of the corresponding muscle of the patient is collected; and according to different control algorithms, the patient drives robot to realize the active training. According to the sitting and lying type lower limb rehabilitation robot disclosed by the invention, the traditional physical therapy, occupational therapy and kinesitherapy are organically combined, so that the patient rehabilitation effect can be effectively improved, and the desire of the patient to actively participate is enhanced.