FIELD: chemical technology. SUBSTANCE: before final drying and their storage particles of ammonium nitrate are covered by aqueous solution of at least one inorganic salt which produces salt hydrates with at least one molecule of crystallization water, said covering is carried out by spraying. Particles are dried till water content is equal or less than maximal amount of crystallization water which may be bound with mentioned above inorganic salts. Aqueous solutions (magnesium nitrate and/or calcium nitrate being preferable) are sprayed on particles of ammonium nitrate, quantity of solution is 0.1-3 weight % of weight of particles to be covered. By using of magnesium nitrate particles of ammonium nitrate are dried till water content is equal or less than that in compound Mg(NO3)2•6H2O, where molar ratio of H2O and Mg(NO3)2 is equal to 6 or less. Proposed coating comprises at least one inorganic salt which has at least one molecule of crystallization water, its quantity being 2-6 moles for magnesium nitrate, and 2-4 moles for calcium nitrate. EFFECT: desired coating prevents deterioration at storage. 9 cl, 4 tbl
