The invention discloses a long-distance transmission system for a robot. The long-distance transmission system for a robot comprises an input rotary table, a tightening regulating component, a first Bowden cable, a second Bowden cable, a first guiding wheel component, a second guiding wheel component, an output rotary table, a first Bowden cable tube fixing part, a second Bowden cable tube fixing part and a rack; the input rotary table is fixedly connected with the output terminal of a power output part, and the output rotary table is connected with a corresponding driven joint component; two parallel circular arc grooves are formed in the circumferential surface of the input rotary table, and two parallel circular arc grooves are also formed in the circumferential surface of the output rotary table; and the first and second guiding wheel components are fixed to the rack. The long-distance transmission system for a robot has the advantages that the Bowden cable is utilized for completing long-distance transmission of motor power, inertia of a mechanical arm of a rehabilitation robot is reduced, and system control and system power are optimized; and the motion range during transmission of a joint of the robot is effectively expanded.