Abstract Background: KQS1 is a bioactive peptide derived from red bean that has shown anti-allergic activity in preclinical models; however, its effects on mast-cell responses and the epigenetic mechanisms potentially involved remain incompletely defined. Objective: To investigate whether preventive oral administration of KQS1 attenuates food-allergy-associated responses and its mechanism. Methods: An OVA-induced murine food-allergy model was established with preventive oral gavage of KQS1.