The aim was to study the kinetics of the release of polyphenolic compounds from chokeberry during digestion in the stomach and small intestine. In order to determine the amount of polyphenolic compounds before the digestion, chemical and enzyme-assisted extraction were performed. In vitro digestion of chokeberry was conducted by simulating digestion in the stomach and small intestine, in different time periods (5, 10, 15, 20, 30, 60 and 120 min). Identification and quantification of polyphenolic compounds was performed using the RP-HPLC method (Reversed-Phase High-Performance Liquid Chromatography). Phenolic acids (neochlorogenic and chlorogenic acid), anthocyanins (cyanidin-3-galactoside, cyanidin-3-glucoside, cyanidin-3-arabinoside and cyanidin-3-xyloside) and flavonols (quercetin-3-rutinoside, quercetin-3-galactoside and quercetin-3-glucoside) were identified in chokeberry before and after the digestion in the stomach and small intestine. Before digestion, anthocyanins (66 %) were present in the highest percentage in chokeberry, followed by phenolic acids (26%) and flavonols (8%). A similar percentage distribution was found after digestion in the stomach (anthocyanins 58%, phenolic acids 36%, flavonols 6%), while the total distribution in the small intestine differed (phenolic acids 56%, anthocyanins 27%, flavonols 17%). These changes are possible due to different pH values during digestion in the stomach and small intestine. The obtained data (the amount of polyphenolic groups released during digestion \((c_{t)})\) vs time (t) were analyzed by non-linear regression using modified equations of the first and second order. The rapid release time of polyphenols was predicted (\(t_{1/2}\) first order: stomach 0.94 - 2.31 min, small intestine 0.82 - 4.10 min; second order: stomach 0.63 to 1.02 min, small intestine 0.77 to 2.50 min).The high correlation between \((C_{00})\) predicted by the model and experimental values indicated the possibility of using equations to analyze simulated digestion.