The invention relates to a submerged nozzle argon injection control method of a continuous casting crystallizer. The submerged nozzle argon injection control method of the continuous casting crystallizer comprises the steps that S1, the theoretical volume flow rate of injected argon at the temperature of 25 DEG C is calculated based on the width K and thickness H of the section of a cast blank ofa wide and thick plate to be produced and the drawing speed Vc of the cast blank according to a calculation formula (please see the specification for the formula), wherein eta indicates the ratio of the cross section of the argon flow in an submerged nozzle to the cross section of the submerged nozzle, and eta=0.05-0.15; and S2, the argon injection speed is controlled and adjusted according to thetheoretical volume flow rate obtained through calculation, and at this moment, a three-vortex flow field is formed by molten steel in the crystallizer. Preferably, the submerged nozzle argon injection control method further comprises the step that S3, argon bubbles jet out of an outlet of the submerged nozzle are gathered in an area which is in a fan shape relative to the projection of the wall of the wide edge of the crystallizer by controlling and fine adjusting the volume flow rate of the argon. By adoption of the submerged nozzle argon injection control method of the continuous casting crystallizer, the argon delivery speed can be controlled, and the flaw detection qualification rate of produced cast steel plates reaches 98% or over.