The article presents the data of the results of research conducted in the conditions of the educational and scientific practical center of the Mykolaiv NAU during 2016-2019 yrs with four varieties of winter barley. It was determined the influence of foliar top dressing with modern biopreparations and growth-regulating preparations in the main periods of vegetation of plants on grain quality indicators. It was found that the protein content in grain depended and varied on the preparation taken for processing barley crops, the time of top dressing, varietal characteristics of winter barley, and significantly on the weather conditions of the growing year. Similarly, under the influence of these factors, other indicators of grain quality changed.