An automatic label supply device comprises a mounting base, a mounting transverse plate which is arranged on the mounting base, a mounting vertical plate which is fixedly connected with the back side of the mounting transverse plate, a label lifting mechanism, a label suction mechanism and a label claw deliver mechanism, wherein the label lifting mechanism adopts a lifting servo motor to drive a label tray to ascend and descend; the label suction mechanism adopts a rotary cylinder to drive a suction disk cylinder to rotate, a suction disk rotates with the rotary cylinder and ascend and descend under the driving of the suction disk cylinder; a gas claw cylinder of the label claw deliver mechanism controls a gas claw to receive the label which is sucked on the suction disk. One label deliver process can be accomplished by the device, the labels can be sucked one by one, the device is cooperated with a label delivery mechanism to automatically deliver the label to the labeling position of a package streamline, and the automation of labeling supply is achieved. The device is compact and reasonable in structure, and small in occupied space.