The method of synthesis for 2,4,6-triiodoresorcine comprises a stage of resorcin (I) iodination with iodine chloride in the presence of hydrochloric acid as a catalyzer. The reaction mixture is allowed to stand for 1 h at the temperature of 20-5 C. The precipitate is filtered and dried at 50 C. Triiodoresorcine yield is 93.6% (crystallized from CCl4).