The invention relates to a super advanced double-phase stainless steel smelting process method of a CD3MWN material. According to the invention, internal control components during double-phase stainless steel smelting is designed, wherein C is less than or equal to 0.030 wt%, Si is less than or equal to 0.90 wt%, Mn is 1.20-2.50 wt%, P is less than or equal to 0.020 wt%, S is less than or equal to0.015 wt%, and Cr is 26.2-27.5 wt%, Ni is 6.2-7.6 wt%, Mo is 2.2-3.4 wt%, Cu is less than or equal to 0.80 wt%, W is less than or equal to 0.80 wt%, N is 0.32-0.38 wt%, B is 0.0010-0.0100 wt%, Ba is0.0002-0.0100 wt%, and Ce+La is 0.005- 0.030 wt%; and %Cr+3.3 (%Mo+0.5%W)+16%N is less than or equal to 45, the content of trace elements B, Ba, Ce, and La can be precisely controlled; the N content is increased to 0.30% or more, and at the same time, nitrogen holes in the casting can be avoided; and the content of harmful elements such as sulfur, oxygen, hydrogen and the like is minimized to improve the purity of the molten steel. The cast casting has high strength and excellent corrosion resistance. In the stainless steel, a ferrite phase and an austenite phase are close to 50%, the castinglife is prolonged. the production costs are greatly reduced, and purposes of energy saving and environmental protection can be realized.