The invention relates to a preparation method of a vanadium-nitrogen alloy and belongs to the technical field of vanadium-nitrogen alloys. The method comprises the following steps: 1) a vanadium-nitrogen compound is smashed and uniformly mixed with a reducing agent, a nitrogen increasing agent and a catalyst in proportion, and the substances are stirred for 1.5-3 h; a binder and water are mixed uniformly in proportion; the two mixtures are mixed uniformly for standby application; 2) the finally obtained mixture in step 1) is pressed for the first time and subjected to second pressing forming under pressure higher than the first pressing pressure, a formed pressed product is naturally air-dried; 3) the pressed product air-dried in step 2) is subjected to drying, reduction, carbonization nitriding and nitrification sintering, and the vanadium-nitrogen alloy is obtained. Stirring time after raw materials are mixed with water can be shortened effectively, the binder is dissolved completelyand plays the binding role sufficiently, one-time pelletizing rate is increased, initial strength of pellets is improved, and curing effect is improved; surface quality and grade of vanadium-nitrogenare improved.