FIELD : nanotechnology; medicine.SUBSTANCE : invention relates to the field of nanotechnology, medicine, pharmacology. Method for preparing nanocapsules of diacamph in guar gum is characterized in that guar gum is used as nanocapsule coating, at the same time, diacamph is added in portions to a suspension of guar gum in butyl alcohol containing E472c as a surfactant, with a mass ratio of diacamph : guar gum 1 : 1, or 1 : 3, or 1 : 2 the mixture is stirred, then petroleum ether is added, the resulting nanocapsule suspension is filtered and dried.EFFECT : method for producing nanocapsules of diacamph in guar gum is proposed.1 cl, 3 ex