The aim of this study was to compare the quality of life of patients under home mechanical ventilation (HMV) for restrictive lung disease, with the quality of life of patients with chronic obstructive pulmonary disease (COPD), having similar decrease in forced expiratory volume in one second (FEV1), but not receiving HMV. Sixteen patients who were receiving intermittent HMV (six post-tuberculosis, four post-poliomyelitis, two neuromuscular diseases, two kyphoscoliosis, two obesity-hypoventilation syndromes) were compared to 15 COPD patients who were receiving only usual conservative treatment, including long-term oxygen therapy. Dyspnoea scores, anxiety, depression, and psychosocial scores, as well as a panel of functional parameters were measured. The two groups did not differ in terms of functional impairment. However, patients under HMV had much better scores for anxiety, depression, and adjustment to illness than COPD patients. Scores for dyspnoea at rest were also better in the HMV group, but showed no relationship to quality of life. In spite of a cumbersome and intrusive type of treatment, patients under home mechanical ventilation for predominantly restrictive lung disease were found to have a better quality of life than chronic obstructive pulmonary disease patients under conservative therapy. In the first group, a longer history of coping with a chronic disease and the perception that medical intervention is effective may in part account for this difference.