Distonia Segawa disease is a guanosine triphosphate cyclohydrolase I deficiency (DYT5). Objectives: study clinical, paraclinical, treatment Segawa desease. Method: one case report. Results: A 8 year-old girl who presented with gait disturbance is characterized by leg stiffness and tendency to walk in an equinus posture, gait tends to worsen later in the day, muscle tone is increased and deep tendon reflexes are exaggerated, routine blood investigations including haemogram, total and white blood cell count, blood sugar, liver and renal funtion, MRI brain were all normal. Confirmed the diagnosis by clinical and sustained improvement when treated with levodopa. Conclusion: Segawa syndrome is a rare genetic disorder autosomal dominant 14q22.1 characterized by an uncoordinated, abnormal gait diurnal fluctuation and dopamine-responsive dystonia.