Warning device on highway

The utility model relates to a warning device on a highway. The warning device comprises a base capable of walking along a highway guardrail, a manipulator, and a driving device for driving the manipulator to act; a driven wheel, a driving wheel and a motor for driving the driving wheel to rotate are arranged in the base; and one end of the manipulator is connected with the driving device and hinged with the base through a hinge, and a warning light is arranged at the other end of the manipulator. The warning device has the advantages of simple and compact structure, convenience in use and high reliability, and can walk automatically by taking the highway guardrail as the track; after the warning device walks backwards for a set distance, the manipulator is unfolded automatically, and the warning light on the manipulator can warn vehicles behind; and when the warning is canceled, the manipulator is folded under the control of a remote controller, and then the warning device goes back to the initial position.