We report the case of a child with difficulties to control epilepsy and celiac disease, diagnosed soon after the onset of the seizure disorder. Seizure frequency and pattern, in addition to electroencephalogram record were suggestive of Lennox-Gastaut syndrome. Diagnosis of celiac disease was determined by positive anti-endomysium and anti-transglutaminase tests, and abnormal jejunal biopsy. Gluten-free diet, started soon after the diagnosis, led to progressive seizure control, allowing significant decrease in dosage of anti-epileptic drugs. This case corroborates the importance of serological screening tests for celiac disease, at least in patients with difficult to control epilepsy.