The invention provides an automatic control method for extracting coarse vanadium slag from vanadium-containing molten iron. The method comprises the following steps: timely obtaining needed coolant dosage and total oxygen supply amount through acquired molten iron information and coolant information; and further identifying parameter setting of the coolant and oxygen in respective adding processes, so as to enable the whole vanadium extracting process to be timely, accurately and stably controlled, thereby improving the vanadium extraction efficiency, and stabilizing the product quality.