The invention discloses an electroslag remelting solid slag arc striking agent and an arcing method thereof. The electroslag remelting solid slag arc striking agent consists of the following components in percentages by mass: 3-5% of pre-melted slag, 0.3-0.5% of aluminum particles and the balance of scrap iron. The scrap iron is used as the main raw material of the solid slag arc striking agent, the scrap iron which is machining waste is recycled, the cost is low, secondary pollution does not exist, and the waste is reused; and moreover, resources are saved, the cost is greatly saved, and possibility of environmental pollution is eliminated. The method has the characteristics of simplicity in operation, stable process, high success rate and the like.