Objective: The Zarit Burden Interview has been used in many studies to assess caregiver burden in family caregivers of patients with amyotrophic lateral sclerosis, but the factor structure of the Zarit Burden Interview in the caregivers of amyotrophic lateral sclerosis patients is unknown. The aim of this study was to explore the factor structure of the Zarit Burden Interview in family caregivers of amyotrophic lateral sclerosis patients using exploratory factor analysis.