The invention discloses a fertilizer for cultivating trees. The cultivation fertilizer comprises the following raw materials in parts by weight: 120-130 parts of chicken manure, 100-120 parts of lake grass, 70-90 parts of sawdust, 60-70 parts of fermented corncob, 30-35 parts of meat and bone meal, 25-30 parts of peanut cake, 20-23 parts of pulverized fuel ash, 12-15 parts of perlite, 10-12 parts of pelelith, 23-26 parts of urea, 20-24 parts of calcium superphosphate, 17-19 parts of potassium dihydrogen phosphate, 10-15 parts of ground phosphate rock, 4-5 parts of ferrous sulfate, 2-3 parts of magnesium sulfate, 2-3 parts of borax, 6-9 parts of EM (Effective Microorganism), 10-15 parts of soil conditioner and a proper amount of water. According to the fertilizer for cultivating trees, the fertilizer utilization rate can be improved and the fertilizer can achieve the effects of increasing both output and income. Since excrements are under the blazing sun for quite a long time, the stink of excrements is removed. The fertilizer contains abundant active organic components, thus being capable of activating soil and increasing the quantity of beneficial microbes; after being applied to soil, the fertilizer can immediately provide quick-acting nutrients needed by the growth of plant, and can also improve the soil.