The invention relates to AOP premix, soft-shelled turtle feed containing the AOP premix, a preparation method and an application. The AOP premix comprises, by weight, 39.6-50 parts of sodium alga acid, 0.1-0.3 part of chitosan, 5-15 parts of lactobacillus acidophilus, 5-15 parts of magnesium phosphate, 8-10 parts of sodium acetate, 0.5-1.5 parts of potassium sorbate, 10-20 parts of decanoylacetaldehyde, 2.5-7.5 parts of lauryl aldehyde and 2.5-7.5 parts of disease-resistant growth promoting agent. The soft-shelled turtle feed comprises, by weight, 69.2-77 parts of animal source protein matter, 15-21 parts of bean pulp, 1-3 parts of sesame seed meal, 1-3 parts of vital gluten, 1.8-2 parts of unhulled rice buds, 1-3 parts of vegetable oil and 0.8-1.2 parts of the AOP premix. The AOP premix has the good disease-resistant growth promoting effect and can enhance the fish body immune function, remarkably increase the survival rate and yield of soft-shelled turtles and remarkably improve the quality of the soft-shelled turtles. The soft-shelled turtle feed is proper in nutrition matching, the preparation method is easy and practicable, cost is low, food calling performance is high, palatability is good, absorption is quick, and digestion is easy.