A protective guard for the arm of a welder which includes both padding and insulation to cushion and protect the arm from heat in activities such as welding or similar tasks. The guard includes a pad and a flexible flap which is applied over the upper surface of the arm in order to more completely protect the arm above the area normally covered by the cuff of the standard welding glove. The guard may be easily applied by the use of elastic straps attached to the pad and the pad is sufficient length to extend past the elbow in order to prevent both the arm and elbow from coming into contact with heated objects, while the flexible flap is formed to allow complete bending of the arm without binding at the inside of the elbow. At least the outer portions of the guard are preferably formed of durable heat-resistant materials, such as leather.