The invention discloses a fertilizer special for maintaining lawns and a preparation method thereof. The method comprises the following steps: weighing, mixing and stirring citric acid, zinc sulphatepowder, copper sulphate powder, manganese sulphate powder, ferrous sulphate powder, borax powder, ammonium molybdate and water at a temperature of 80-90 DEG C for 40-60 minutes to prepare trace element chelate fertilizer liquid; weighing, mixing and stirring polyvinyl alcohol, cornstarch and dicyandiamide powder at a reaction temperature of 80-90 DEG C for 40-60 minutes to prepare bonding liquid;uniformly mixing the trace element chelate fertilizer liquid and the bonding liquid according to a mass ratio of 1:4 for spare; weighing, drying, crushing and screening pyrobituminous shale residue, furfural residue, calcium carbonate, magnesium sulphate, urea, diammonium phosphate and potassium sulphate by a screen of 100-120 meshes; uniformly mixing; adding the mixture to a pelletizer; and spraying the mixed liquid to granulate so as to obtain the fertilizer special for maintaining lawns. The invention has the advantages of enough nutrients, good slow release, and the like, prolongs the nutrient-supplying time and protects the biological environment.