The invention provides a repellent for natural enemy insects. The repellent comprises an active substance 2-ethyl-1-
hexanol. The concentration of the active substance is at least 1 mu g / mu L; the active substance is derived from resource
insect female
mucilage gland secretions with a repelling effect on natural enemy insects, and the resource
insect female
mucilage gland secretions cover the self-oviposition surface of the resource insects. The invention also provides an application of the repellent. The repellent is used for repelling natural enemy insects with parasitic ability to non-adult resource insects. The natural enemy insects comprise
hymenoptera insects; the resource insects comprise tussah, silkworms and castor silkworms. Applying the repellent of the natural enemy insects to the non-adult surfaces of the resource insects or to the growth environment of the resource insects. According to the invention, 2-ethyl-1-
hexanol is used as an active substance to prevent parasitic wasps from parasitizing various resource insects, so that the technical purpose of effectively, safely and efficiently preventing and controlling the parasitic wasps is achieved, the economic benefit of the resource insects is improved, and the insecticide has the advantages of greenness,
environmental protection and
low toxicity.