Grapevine, although not one of the most widespread fruit species, holds significant importance for the Republic of Croatia. Croatian wines have become increasingly recognizable in recent times, indicating the potential future economic significance of viticulture in Croatia. In recent years, problems with phenolic ripeness of grapes have become more prominent, primarily attributed to climate change. The polyphenol composition of grapes is of exceptional importance, mainly due to the impact of certain polyphenols on the sensory characteristics of wine. In the search for sustainable and environmentally friendly solutions, products containing inactive dry yeasts with elicitor effects, which stimulate the formation of polyphenols, have emerged in recent years. The aim of this study was to examine the impact of inactive yeasts of the species Saccharomyces cerevisiae on the polyphenol composition of the indigenous Croatian grapevine variety 'Babić crni'. The research was conducted in the growing area of Jadrtovac – Donje polje, and the analyses were carried out at the Faculty of Agriculture in Zagreb. The investigated parameters included: cluster mass, sugar content, total acidity, pH value, concentration of polyphenols and organic acids, and nitrogen content in the must. The study showed that treatment with inactive yeasts "LalVigne® AROMA" can significantly affect the properties of the 'Babić crni' grape variety, suggesting potential for improving wine quality. Significant differences were found between treated and control samples in cluster mass, nitrogen content in the must, and the content of individual polyphenols in grape skins. The study did not find significant differences in total acidity, actual acidity, organic acid content, and sugar content in the must.