Preparation method of hot forging die steel

The invention relates to the field of steel and iron manufacturing, and discloses a preparation method of hot forging die steel, which comprises the following steps: step a, steel raw materials are put into an electric furnace for smelting to obtain a steel ingot, the weight ratio range of vanadium to carbon in the steel ingot is 2.0-2.5, the weight ratio range of chromium to molybdenum is 3.0-3.5, and the weight ratio range of chromium to molybdenum in the steel ingot is 2.0-2.5; the sum of the weight ratios of the vanadium element, the molybdenum element and the chromium element is not less than 7.0%; b, the steel ingot is forged based on the preset forging ratio and the preset forging temperature, and a forging stock is obtained; c, the forging stock is subjected to normalizing heating at the first preset temperature and then cooled, solution treatment and spheroidizing annealing treatment are sequentially conducted at least once at the corresponding temperature and the corresponding heat preservation time