Glucose Transporter Type 1 Deficiency Syndrome (GLUT1DS) is a rare disorder with a broad spectrum of neurological manifestations. The ketogenic diet (KD) is, to date, the gold standard treatment. Behavioral problems, well recognized in patients with chronic conditions, have not been, so far, deeply investigated in GLUT1DS patients. We performed an exploratory study to assess the risk of emotional and behavioral problems and investigated the potential role of influencing factors related to the pathology itself or KD treatment.