The invention provides a novel driving rear-mounted lower extremity exoskeleton robot. The robot comprises a back assembly (1), two hip joint assemblies (2), two thigh rod pieces (3), two knee joint assemblies (4), two calf rod pieces (5), two ankle joint assemblies (6) and two foot assemblies (7), wherein the hip joint assemblies (2), the two thigh rod pieces (3), the two knee joint assemblies (4), the two calf rod pieces (5), the two ankle joint assemblies (6) and the two foot assemblies (7) are sequentially connected to the two sides of the back assembly from top to bottom in sequence. Therobot is high in structural function adaptability, and the external dimension and size are flexible and meet the human body bionic design. According to the robot, a power source is completely placed at the back, power is transmitted to the hip joints through a synchronous belt, a transmission mechanism is simple, transmission is accurate, the transmission efficiency is high, the size of the two sides is effectively reduced, and the robot occupies a small space and is more portable.