OBJECTIVE: To describe the quality of life (QOL) and care burden of caregivers of ventilator-dependent amyotrophic lateral sclerosis (ALS) patients and to compare the QOL of ALS caregivers with that of dementia caregivers. METHOD: Ninety-one pairs of ALS patients and their caregivers were interviewed. Patients were asked to provide their age, sex, time since diagnosis, and length of ventilator use, as well as complete the ALS functional rating scale-revised (ALSFRS-R). Caregivers were asked to provide baseline demographic data including age, sex, education level, marital status, link with the patient, occupation, care time, substitute caregiver, and personal caregiver. The short form-36 (SF-36) and burden interview (BI) were also administered to evaluate caregivers' QOL and care burden. T-tests, ANOVA, and Pearson correlation coefficients were used for data analysis. RESULTS: Ninety-one pairs of patients (men 69.2%, women 30.8%) and caregivers (men 24.2%, women 73.6%) completed the study. The mean SF-36 physical component summary (PCS), mental component summary (MCS), and total scores of caregivers were 131.5+/-13.2, 114.3+/-17.6, 245.8+/-28.2, respectively, which showed that the QOL of ventilator-dependent ALS patients was decreased. The BI score was 52.8+/-17.8, which meant that caregivers were heavily burdened. The SF-36 total and MCS were correlated with the BI. Care time was an important factor that influenced QOL and care burden. QOL was significantly lower for ventilator-dependent ALS caregivers than for dementia caregivers. CONCLUSION: This survey revealed the poor QOL and heavy burden of ventilator-dependent ALS caregivers, which necessitates social interventions including strategies about care time.