The objective of this experiment was to measure the standardized ileal digestibility of crude protein and amino acids in hominy feed, corn gluten meal, corn gluten feed, and corn germ meal and to compare these values to the digestibility of crude protein and amino acids amino acids in corn and distillers dried grains with solubles (DDGS). Results showed that the digestibility of most amino acids were greater (P < 0.05) in hominy feed and in corn gluten meal than in the other ingredients, whereas the digestibility of most amino acids in corn gluten feed was lower (P < 0.05) than in the other ingredients.