The article presents the results of the study of antioxidant properties of plant powders of common elder (Sambucus nigra L.) and little-leaved linden (Tilia cordata Mill) flowers. Powders were put to the confectionery fat at a concentration of 1 and 2% by weight of fat. The fat sample with no additives was as a control. The experimental studies were conducted in the model conditions of the accelerating kinetic method by the temperature of (90 ±2) °С with free access to oxygen. The change of fat quality was controlled by the content of oxidation products – primary (peroxidation number), secondary (benzidine number) and products of hydrolysis (acid number). Among the studied plant ingredients, the powder of common elder flowers, at a concentration of 1.0% by weight of fat, provided the reduction of the quantities of peroxide number in 1.3–1.55 times. Increased concentrations of powder to 2.0% led to the creation of the antioxidant effect in 1.34–1.60 times. According to the peroxide value, the powder of little-leaved linden flowers (1.0%) exceeded the effectiveness of the common elder flowers (1.0%) in 1.1 times. In the sample of fat with this additive, the content of peroxides is reduced to 1.36–1.72 times for the entire period of storage. In neighbor value of the degree of the primary oxidation in the sample of fat with the addition of 2.0% powder of little-leaved linden flowers, the number of peroxides in 1.39–1.83 times compared to 1.0% of this additive, nevertheless was managed to reduce. The benzidine number of confectionery fat due to the addition of these herbal powders turned lower in 1.2–1.7 times during monitoring and acid number – in 1.15–2.80 times. Thus, it is proved that their adding to the confectionery fat allows to slow down the processes of oxidation and hydrolysis of fat in 1.20–1.83 times regarding the control sample. The powder of little-leaved linden flowers showed higher efficiency. The obtained results make it possible to conclude that the use of studied additives as the plant ingredients in the production of fat-containing flour confectionery products of high biological value with a view to extending its storage is possible.