The invention belongs to the technical field of fertilizer preparation, in particular to preparation of citrus proprietary formula fertile being suitable for purple shale soil and applications thereof, which is characterized in that the fertilizer comprises the following effective elements according to pure nutrient in weight percent: 14-18% of nitrogen, 8-10% of phosphorus pentoxide, 8-12% of potassium oxide, 8% of humic acid, 0.05-0.08% of pure boron, and 0.6-1% of zinc oxide; or 12-15% of nitrogen, 6-10% of phosphorus pentoxide, 12-15% of potassium oxide, and 8% of humic acid. The citrus proprietary formula fertile is more suitable for citrus orchards in Three Gorge area, and solves the problems of super high citrus density in the area, single fertilizer types, unreasonable fertilizer proportioning, low fertilizer utilization, and decreased output and quality and the like. By the invention, the yield of the Newhall navel orange is increased by 38.53% and 23.04%, the yield of the Robertson Navel orange is increased by 10.68% and 21.14%, and the yield of the Cara Navel orange is increased by 25% and 15.38% for two consecutive years; and the content of fruit vitamin C is improved by 2-5mg/100g, and the fruit commodity is good.