In this study was to investigate the influence of storage time, light and temperature on stability of polyphenols in sour cherry (Prunus cerasus) and blackberry (Rubus fruticosus), were harvested in western Serbia (Rasinski region). Total phenol content was monitored in the fruit extracts during 23 days stored at 7°C under darkness and 90 days storage at 23°C in oxygen. For analyzed extracts, first-order reaction kinetics was established for the degradation process of polyphenols. The temperature dependence of the polyphenols degradation rate constants was expressed by the temperature coefficients Q10 of the process. It is found that the Q10 values of polyphenols degradation in sour cherry and blackberry extracts were 1.247 and 3.239, respectively