The use of biostimulating microfertilizers during foliar feeding makes it possible to reduce the introduction of mineral fertilizers into the soil. This method of fertilization is safe for the environment because the nutrients are applied in controlled amounts. The purpose of our research was to evaluate the effect of foliar fertilization of apple trees on productivity, commercial quality of fruits and economic efficiency. As a result of the research, a positive effect of the use of biostimulants in intensive apple plantations of Gala, Pinova, Fuji, Red Jonaprinz varieties was established. In the course of research, biological preparations of the company "Timak Agro Ukraine" of the brands Maxifruit, Fertileader Elite, Fertileader Axis were used. Application of these drugs was carried out according to the scheme: when the average size of the fruits was 30 mm, foliar treatment with biostimulants at the rate of 3 l/ha was carried out, followed by repetition after 10 days. To assess the effect of the biological preparation, apples were sorted into fractions according to the diameter of the fruit - less than 60 mm, 60-69 mm, 70-75 mm, more than 75 mm. They also calculated the yield and evaluated the marketable quality of the harvested fruits. It has been proven that foliar treatment of trees with biological preparations helps to increase the size of fruits, which in turn reduces the number of non-standard products (fruits with a diameter of less than 60 mm) and significantly increases the share of fruits larger than 70 mm. Due to their anti-stress properties, biological preparations had the maximum effect on the fruits of the Pinova variety, which is not sufficiently resistant to high temperatures and low air humidity, increasing the share of fruits larger than 70 mm by 21.4 % compared to the control and the small-fruited Gala variety, for which this increase was equal to 12.9 %. It was established that as a result of increasing yield, improving the size, and therefore the marketability of fruits, the average sale price increased, which in turn increased the economic efficiency of fruit cultivation. Key words: apple tree, variety, foliar fertilization, product quality, yield, economic efficiency.