Patients with neuromuscular scoliosis (NMS) are frequently considered at high risk for postoperative complications based on their underlying disease and comorbidities. Postoperative complications include prolonged mechanical ventilation (MV), defined longer than 72 h, at the paediatric intensive care unit. The objectives of this retrospective study were to assess the incidence of prolonged MV in patients with NMS following scoliosis surgery and to identify predictive risk factors. A total of 46 consecutive patients underwent surgical spinal fusion and instrumentation for progressive NMS. Prolonged MV was required in seven of 46 patients (15%). The only risk factor for prolonged MV was a decreased preoperative pulmonary function. Forced expired volume in 1 s and vital capacity were significantly decreased in patients with MV >72 h compared with patients with MV <72 h. Routine preoperative pulmonary function testing may reveal important information with regard to restrictive lung disease in the preoperative assessment of patients with NMS and predict the early postoperative clinical course.