An in vitro method was used to determine ruminal degradability of starch (IVRDS) in a set of cereal grains. The set included 9 feed samples, including 2 samples of ground wheat, 2 samples of wheat treated with sodium hydroxide, ground barley, barley treated with sodium hydroxide, 2 samples of ground oats and ground maize. Ruminal degradability of starch was assayed by the feed fermentation for 2, 4, 6, 16 and 24 hours. A significant difference in starch degradability was found between treated and untreated ground samples after 2-hour fermentation, 4-hour fermentation and 6-hour fermentation. On the basis of the rate of ruminal degradability of starch the order of cereal grains was as follows (from the highest to the lowest value): ground oats, ground wheat, ground barley, ground maize, wheat and barley treated with sodium hydroxide.