The invention discloses a fertilizer special for peanuts and a preparation method thereof. The fertilizer special for peanuts is prepared from the following raw materials by weight: 65-67 parts of peanut shell organic fertilizer, 9-15 parts of plant ash, 6-7 parts of biological bacterial fertilizer, 2-3 parts of humic acid chelate fertilizer, 0.02-0.03 part of rare earth micronutrients, 6-7 parts of wormcast, 4.5-5 parts of ammonium dihydrogen phosphate, 1.3-1.6 parts of potassium sulfate, 0.13-0.16 parts of borax, 0.03-0.05 part of ammonium molybdate, 1.4-1.9 parts of calcium superphosphate, 0.05-0.07 part of ferrous sulfate, 0.05-0.07 part of zinc phosphate, 0.05-0.07 part of manganese sulfate, and 2-3 parts of an adhesive. Through reasonable proportioning of organic matters, inorganic matters, microbial bacteria, trace elements, rare earth elements and other nutrients, the fertilizer special for peanuts provided by the invention can increase the organic matter content of soil, loosen and improve soil, enhance soil fertility, strengthen the disease resistance of plants, increase crop yield and improve crop quality, has long effective period, lasting and mild fertility, can satisfy the requirement of mechanical operation, and has the advantages of low input, high output, high benefit and no pollution, etc.