FIELD: chemistry. SUBSTANCE: present invention relates to a method of synthesis 5,11,17,23,29,35,41,47-octa-tert-butyl-49,50,51,52,53,54,55,56-octaoxicalix[8]arene 1, which involves reaction of para-tert-butylphenol with formaldehyde in form of 40 % aqueous solution in an inert gas atmosphere with heating up to temperature of 220 °C. Three-fold molar excess of formaldehyde is used, and per 1 kg of calix[8]arene 1, an organic solvent of an aromatic series is added in amount of 20 ml and excess formaldehyde is trapped with a scrubber with the possibility of reusing the reagent. EFFECT: disclosed method enables to trap toxic emissions of formaldehyde and uses minimal amounts of organic solvent, which generally significantly reduces harmful environmental consequences for the environment and human health. 7 cl, 2 dwg.