The aim of this work was to determine digestibility of native and modified both potato and com starches. Furthermore, we investigated the effect of sweeteners addition on amylolysis of these starches. We proved that enzymatic susceptibility of starch is dependent on both raw material and method of modification. The results of the experiment indicate high digestibility (>94%) of modified starches, which have been subjected to hydrothermic processing (Adamyl CS, Adacorn CS). However native starches and Adamyl HS and Adacorn HS, which have not subjected to hydrothermic processing were less digestible. Furthermore, we confirmed, that sweeteners addition does not influences on in vitro starch digestibility.