The invention relates to the technical field of fertilizer processing, in particular to a Shatian pomelo leaf fertilizer and a preparation method thereof. The Shatian pomelo leaf fertilizer is mainlyprepared from raw materials, such as human and animal manure, biogas slurry and biogas residue, trichilia connaroides leaves, radix peucedani, fructus psoraleae, paulownia leaves, ephedra equisetina leaves, an adhesive, an enzymic preparation, magnesium lignosulfonate, ammonium molybdate, calcium borate, rice washing water, ethylene, expired milk by the steps of performing raw material processing,fermenting, performing enzymolysis, filtering, blending and the like. The Shatian pomelo leaf fertilizer is rich in nutritional ingredients, has bacterium killing and insect killing effects, reducesplant diseases and insect pests, reduces utilization rate of pesticides and fertilizer, remarkably increases the per mu yield, the soluble solid content and the sugar content of Shatian pomelo, shortens the fruit ripening time and reduces the astringency of the Shatian pomelo; the fruit is high in nutritional value, large in size, high in water content, thin in fruit peel and sweet and delicious in fruit pulp; and moreover, the Shatian pomelo leaf fertilizer is simple in preparation process and easy to produce.