The glutamine-rich peptides were hydrolysis from whey， rice and wheat， respectively. The optimal peptides were selected according to their protein recovery rate， amide nitrogen content， molecular weight distribution and antioxidant activity（hydroxyl radical scavenging activity and oxygen radical absorption capacity）. The tolerance of three optimal peptides to gastrointestinal simulated digestion was further studied to conform the packing materials and the best raw material for the preparation of glutamine-rich peptides. Results showed that whey peptides （Trypsin group）， rice peptides （Flavorazyme group） and wheat peptides （Flavorazyme group） were selected as the optimal peptides and were applied for the further in vitro simulated digestion. Besides， enteric-coated capsules were used as the packing material of whey peptides while ordinary capsules were used for the packing of both rice peptides and wheat peptides. The amide nitrogen content of wheat peptides increased to 1.90% after gastrointestinal simulated digestion， and the proportion of small peptides （Mw < 1 ku） was high at 74.59%. There was no significant change in its antioxidant activity with the hydroxyl radical scavenging rate of 22.89% and ORAC value of 1.28 μmol TE/（L·mg） peptides， respectively. Hence， wheat protein was chosen as the best raw material for the preparation of glutamine-rich peptides.