The invention provides a method for smelting high-nitrogen steel by a vacuum induction positive-pressure furnace, belonging to the technical field of smelting of high-nitrogen steel. The method comprises the steps: preparing a smelting material, clearing a crucible, loading a smelting raw material meeting the requirement of smelting a grade of steel; vacuumizing a smelting chamber of the vacuum induction furnace, and starting power transmission to heat a furnace material when the vacuum degree is less than 15Pa, wherein a power is 40 Kw; gradually increasing the power, and after a weld pool occurs, controlling the power to avoid splashing; completely smelting the furnace material, and reducing the power to perform refining to remove O, N, H and the like; starting a nitrogen making machine to introduce nitrogen, and adjusting a pressure in the furnace until reaching a required pressure value so that the saturation solubility of nitrogen is increased; adding the smelting raw material of increasing the partial pressure and a nitrogen-increasing alloy so as to increase the alloy yield; adding a final deoxidizing agent, controlling the temperature of molten steel, and pouring in an electrifying manner. The method is suitable for smelting the grade of steel requiring that the content of nitrogen is more than a defined numerical value or control range, and is capable of achieving the purposes of accuracy in component control, and high and stable nitrogen yield. The method has the advantages that the nitrogen yield reaches above 99 percent, particularly smelting high-nitrogen steel with nitrogen content up to 2 percent comes true, the components are accurate, and the cost is lower; the method is suitable for largely smelting special steel and steel for medical apparatuses and instruments with nitrogen content of 0.4-1.4 percent.