We describe the case of a 40-year-old woman who was admitted for dyspnea and pitting edema of the lower extremities. Severe type II respiratory failure and right ventricular heart failure were present. Non-invasive positive pressure ventilation (NIPPV) improved the symptoms and blood gas values. Since the results of respiratory function tests and computed tomography indicated neuromuscular disease, muscle biopsy was performed and nemaline myopathy was diagnosed. NIPPV was necessary due to severe hypoxia and hypercapnia caused by severe hypoventilation during sleep; however, daytime NIPPV was stopped within a few days, and the patient was discharged with instructions to continue NIPPV at night only. Since discharge, she has been followed-up on an outpatient basis for 8 years. Adult-onset nemaline myopathy with respiratory failure and right ventricular heart failure as presenting features is rare, and NIPPV can be useful in such cases.