The invention discloses an online spray control system for an insulator, and a robot. The system comprises at least one spray mechanism which is provided with one or more spray guns used for spraying coating to the insulator or an insulator chain. The spray mechanism is fixed to a rotating mechanism arranged in the circumferential direction of the insulator. The rotating mechanism drives the spray mechanism to rotate around the insulator or the insulator chain at a angle within a set angle range. The spray guns can swing in the axial plane of the insulator or the insulator chain. According to the online spray control system for the insulator, and the robot, the rotating mechanism drives the spray mechanism to move in the circumferential direction of the insulator so as to spray the insulator by one circumferential circle, operation is easy and convenient, and the spray mechanism rotates forward and reversely within the certain angle range, so that pipeline twining is effectively avoided; and a lifting mechanism is arranged and can drive the rotating mechanism to move up and down, the spray mechanism is driven to make circumferential movement accordingly, axial movement is also achieved, and the omnibearing spraying effect on the insulator and the insulator chain can be achieved.