A study evaluated porcine in vitro digestion and non-starch polysaccharide (NSP) solubilization of corn and wheat without or with xylanase alone or xylanase plus feruloyl esterase (FE). The enzymes supplied 4000 U of xylanase and 35 U of FE per kilogram of sample. Samples were digested with pepsin at a pH of 2.0 and then with pancreatin at a pH of 6.8. The digested samples were filtered to obtain unhydrolyzed residue, which was then washed using alcohol and acetone. The cereal grains (CGs) before in vitro digestion and the washed unhydrolyzed residues were analyzed for dry matter and NSP. Xylanase improved (P < 0.05) in vitro digestibility of dry matter (IVDDM) for wheat (85% vs. 89%), but not for corn (78% vs. 79%). Addition of FE to the xylanase-supplemented CGs increased (P < 0.05) IVDDM for both CGs, and reduced (P < 0.05) the arabinoxylans in the unhydrolyzed residue for corn, but not for wheat. In conclusion, xylanase product used in the current study is more effective in improving the digestibility of nutrients in wheat than in corn. The FE product used in the current study can improve the efficacy of xylanase in improving the nutrient digestibility of wheat and corn.