FIELD: biotechnology.SUBSTANCE: invention is a method of sterilizing in vitro aspen explants, which includes harvesting woody shoots of adult trees in March-April, distillation of young growing shoots, their phased exposure to chlorine-containing agents, such as 2 % Domestos solution for 8 minutes and 10 % Alaminol solution for 10 minutes.EFFECT: invention allows to obtain a high proportion of aseptic viable cultures up to 90 %.1 cl, 1 dwg, 2 tbl