The invention relates to a method for smelting the high-nitrogen steel by pressurizing an electroslag furnace. The method comprises the following steps that: the content and the weight percentage of each raw material of a self-consuming combined electrode parent metal are determined; the self-consuming electrode parent metal is smelted, an alloy pipe after charged with nitro-alloy particles and adeoxidizing agent is welded on the parent metal to produce the self-consuming combined electrode which is welded on a fake electrode and is clamped on the electrode; an arc starting agent is placed into a bottom water tank below the self-consuming electrode; the slag is dried for three to ten hours and is poured into a crystal device, a smelting chamber is sealed; under the condition of nitrogen,the slag is melted with a current ranging from 1000 to 2000A; afterwards, the pressure of the smelting chamber and the cooling water are increased to be 3 to 10 MPa, the smelting is performed with a current ranging from 2000 to 6000A; when the smelting current is reduced to 1000 A, the smelting is over. The method has the advantages that the solid state arc starting slagging way and the self-consuming combined electrode are adopted to perform the smelting in an over-normal pressure sealing smelting chamber, and the problem of the prior art of uneven distribution of nitrogen in the process of preparing high-nitrogen steel is solved, thereby avoiding the remelting and saving the production cost; moreover, the technique method is simple and the smelting effect is good.