We report the case of a traumatic posterior dislocation of the hip in a 3-year-old boy. After a fall in the garden, the boy was brought to our emergency department where an x-ray confirmed a posterior dislocation of his right hip. A successful prompt reduction was performed in the operating room under general anesthesia. This uncommon injury represents an orthopedic emergency and requires prompt reduction to lessen the risk of complications including avascular necrosis of the femoral head.