Background: It is well documented that caregivers of patients with chronic respiratory failure under noninvasive mechanical ventilation (NIMV) are at high risk to develop depression, burden, overload and declining health over time. Objectives: The purpose of the study was to investigate the subjective and objective burden imposed on families of patients under NIMV at home and explore the coping strategies they adopt. Methods: The study population consisted of 50 informal caregivers of patients with chronic respiratory failure under NIMV at home for at least 6 months. The burden of the families, as well as the adaptation strategies, were estimated by a modified version of the Family Burden Questionnaire validated in Greek. Results: Profound objective burden was reported in the field of social relations in 49%, in household management in 43.2%, in financial issues in 31.3% and in employment issues in 29.4% of the families. The subjective burden which the families experienced was usually lower and it was reported in household management in 33.4%, in employment issues in 29.4%, in social relations in 21.6% and in financial issues in 21.5% of the families. The strategies adopted by the families in order to cope with the imposed burden included reorientation of goals in 92.2%, resignation in 88.2%, passivity in 62.7%, hopefulness in 45.3%, ambivalence in 19.6% and guilt in 13.7% of the families. Conclusions: The families of patients under NIMV seem to face major problems (severe burden) in household management and their social relations. Families do not seem to subjectively experience the burden that is objectively recorded and, in the vast majority, they adopt healthy coping strategies.