Although no biomarker has been identified to date, previous studies have reported that about 50% of patients with suspected non-celiac gluten sensitivity (NCGS) had positive first generation anti-gliadin antibodies (AGAs), especially of the IgG class. These antibodies are not specific for NCGS, being also found in CD (80-90%), autoimmune liver disorders (21.5%), connective tissue disease (9%) and IBS (20%), as well as in healthy controls (2-8%), but their finding in patients with a clinical phenotype consistent with NCGS has been regarded as an element supporting this diagnosis. Even though the correlation between AGA IgG and NCGS condition turned out to be statistically significant in most studies, AGA IgG does not seem to be an adequately strong marker for its lacking diagnostic accuracy. However it can partly help the NCGS diagnosis, integrated in the overall management of the patient. Therefore, in the presence of clinical symptoms that suggest NCGS, IgG AGA positivity, together with negative anti-tTG, EMA, and anti-deamidated-gliadin-peptides (DGP) antibodies, NCGS diagnosis might be suspected. Future researches are necessary to identify reliable biomarkers for NGCS diagnosis and to better define clinically and serologically NCGS patients.