The invention discloses a preparation method of environment-friendly nutritional type soft-shelled turtle feed. The method comprises the steps as follows: sweet potato flour, millet flour, royal jelly, fermented waste from slaughter houses, corn germ protein powder, silkworm chrysalises, spirulina powder, herba houttuyniae and an antibacterial halloysite compound are uniformly mixed, water is added, steaming under normal pressure is performed, concentration is performed, potato powder, taurine, chitosan and EM bacteria are uniformly stirred, and granulation and drying are performed, so that the environment-friendly nutritional type soft-shelled turtle feed is obtained. The antibacterial halloysite compound is prepared by the following technology: bamboo powder is added to a sodium hydroxide solution, stirring and filtration are performed, the obtained product is washed to be neutral, halloysite nanotubes and water are added, mixed grinding is performed, water is added, stirring and standing are conducted, a supernatant is taken, a Chinese herbal medicine additive is added, the obtained product is continuously stirred, and filtration and drying are performed, so that the antibacterial halloysite compound is obtained. The feed has rich nutrient substances, is easy to digest and absorb, can meet the growth requirement of soft-shelled turtles, has good suspension and adhesion properties, good water resistance and low loss rate and can reduce feces of soft-shelled turtles and reduce water pollution, so that the fatality rate of soft-shelled turtles is extremely low.