The invention discloses a compound fertilizer special for a flue-cured tobacco variety NC297 and a preparation method and application of the compound fertilizer. The compound fertilizer comprises, by weight, 6-8% of nitrogen, 6-8% of phosphorus and 18-24% of potassium. The compound fertilizer has the advantages that tobacco plants of the flue-cured tobacco variety NC297 planted by the aid of the compound fertilizer can grow well integrally, the topping plant heights can be increased by 9.69-12.50%, the numbers of remained leaves can be increased by 7.11-8.70%, and the lengths and the widths of leaves can be respectively increased by 4.96-8.38% and 3.61-9.39%; the disease resistance can be enhanced, the incidence of weather fleck can be decreased by 16-19.37%, and the incidence of brown spot can be decreased by 17.23-28.38%; the yield per mu can be increased by 10.96-17.83%, and the output value per mu can be increased by 13.30-21.35%; the first-class tobacco proportion can be increased by 14.46-15.05%.