The invention discloses a production method of a steel plate having an iron-zinc alloy plated layer with the extension rate of more than 42%. The production method comprises the following steps: 1) desulfurizing, smelting by a converter and performing alloying treatment; 2) performing continuous casting to prepare a slab; 3) performing rough rolling on the cast slab at the temperature of 1040-1080 DEG C, performing final rolling at the temperature of 880-910 DEG C and curling at the temperature of 670-720 DEG C; 4) performing cold rolling; and 5) performing alloying continuous hot galvanization treatment on a cold-rolled plate under the conditions that the speed of a unit is 90-100m/min, the heating temperature is 820-840 DEG C and the temperature of a rapid cooling section is 490-510 DEG C, taking out of a zinc pot, then cooling a galvanized plate at an upstream section at the cooling speed of 40-60 DEG C/s, and cooling the steel plate after alloying at the cooling speed of 30-50 DEG C/s. By adopting the production method disclosed by the invention, a plated layer on the surface of the extra-super deep drawn GA plate has dense structure and no obvious micro-crack defects, iron-zinc alloy grains on the surface of the plated layer are small and uniform in size distribution, the alloyed plated layer has excellent chalk resistance, and the production method can be widely applied to the production field of steel for automobiles.