The invention discloses an insulating cladding robot coating supply system and a method thereof. The insulating cladding robot coating supply system comprises a coating supply device and a coating control device. The coating supply device comprises a supporting structure piece, a coating barrel pressing plate is arranged on the supporting structure piece, and at least one insulating coating barrelis fixed to the coating barrel pressing plate. The bottom of each insulating coating barrel is provided with a movable pushing disc which is sealed with the insulating coating barrel, the outer sideof the pushing disc is connected with a driving mechanism, and a distance sensor is arranged on the side face, opposite to the bottom, of each insulating coating barrel. Each insulating coating barrelis connected with a coating output pipeline, and each coating output pipeline is provided with an electromagnetic valve. The coating control device comprises a main controller, the main controller isconnected with a driver through a CAN bus, and the driver is connected with the distance sensors. The main controller is further used for controlling the opening degrees of the electromagnetic valvesso as to control the output flow of insulating coating.