The invention discloses a preparation method of a pure natural concentrated type scindapsus aureus nutrient solution. According to the preparation method disclosed by the invention, the pure natural concentrated type scindapsus aureus nutrient solution is prepared by taking a byproduct-kelp leftover materials of a kelp production and processing enterprise as a raw material, establishing a raw material pretreatment method and developing a kelp bio-refinery technology based on coupling of a low-temperature ultrahigh-pressure continuous flow cell disruption technology, a biological enzymolysis technology and a product falling film evaporation technology, so that resource utilization of kelp processing waste is realized, a kelp industrial chain is extended, and the level of a kelp processing technology is increased; a preparation mode of the pure natural concentrated type scindapsus aureus nutrient solution is innovated, and the byproduct of the kelp production and processing enterprise is used as the raw material, so that waste reclamation is realized, the kelp resource utilization efficiency is increased, the environment is protected, the production cost of the nutrient solution is reduced, the practicability is very strong, large-scale production is easy to realize, and the preparation method is a new method which meets industrial requirements and is environment-friendly.