Gastrointestinal food allergies and related diseases, including non-IgE-mediated gastrointestinal food allergies (non-IgE-GIFAs), eosinophilic gastrointestinal disorders (EGIDs), and gluten-sensitive enteropathy, are described in Chapter 16 of the 2021 Japanese Guidelines for Food Allergy (JGFA). These are based mainly on two recently published Japanese guidelines for non-IgE-GIFAs and EGIDs, and international consensus guidelines for a non-IgE-GIFA, food protein-induced enterocolitis syndrome. Herein, the modifications from the previous guidelines, JPGFA2016, and the new information added have been explained in consideration of the current state of clinical practice in Japan.