The invention provides a feed for the economic insect barley worm, its preparation method and application. The feed includes 85-90% of the main material and 10-15% of the auxiliary material in terms of mass percentage; the main material is a mixture of wheat bran, corn flour and soybean powder mixed in an appropriate mass ratio; the auxiliary material It is a mixture of glucose, fish meal, salt, feed multivitamins and cholesterol according to the appropriate and accurate mass ratio. When using the feed described in the present invention to feed barley worms, the digestibility, nutrient conversion rate, and feed utilization rate of the feed are significantly improved, and the feed formula is suitable for raising barley worms in different stages such as larvae, adults, and adults in the oviposition period. Low cost, no pollution to the environment, no residue, green and efficient.