The invention discloses a method for preparing a biological culture material by grinding and stirring before insulated fermentation. The method comprises steps as follows: S1, preparing the biological culture material: a material A contains cottonseed hull, bagasse, distiller's grains, rice bran, pine wood chips, soybean meal, palm kernel shells, decomposed pig manure, sucrose, light calcium carbonate, calcium superphosphate, potassium dihydrogen phosphate, magnesium sulfate and vitamin B; a material B contains spica prunellae slag, coconut shell powder, walnut shell powder, chestnut bracteal shell powder, lotus shell powder, banana stems and leaves, honeysuckle stems and leaves, radix angelicae dahuricae stalks, ginkgo leaves, garlic stalks, cassava stem bits, spartina anglica powder, ageratina adenophora, chrysopogon zizanioides, dicranopteris linearis, pennisetum purpureum, poplar leaves, ganoderma lucidum fruiting bodies, apple pomace, mushroom bran, xylose cinder and cyanobacteria; S2, the biological culture material prepared in the S1 is placed in a grinding and stirring device. A device for grinding and stirring before insulated fermentation is adopted for treatment, so that nutrients in a biological culture solution are easier to absorb, and the nutrients are richer.