Pyridoxine-dependent epilepsy (PDE) is a rare autosomal recessive metabolic disease characterized by seizures in neonates or infants, which is unresponsive to antiepileptic drugs but controlled by pyridoxine. Without prompt treatment, continued seizures and severe encephalopathy result. Mutations in the ALDH7A1 gene encoding α-amino-adipic semialdehyde (α-AASA) dehydrogenase (antiquitin) have been identified as the cause of PDE. We report on a novel ALDH7A1 mutation in a Tunisian child with PDE.