The aim of this study was to identify determinants of functional disability, patient's quality of life (QoL) and caregivers' burden in Huntington's disease (HD). Eighty HD patients participated in the study. Motor and behavioral disturbances as well as cognitive impairment were assessed using motor, behavioral and cognitive parts of the Unified Huntington Disease Rating Scale (UHDRS); Hamilton Depression Rating Scale was used to assess depression. Disability, health-related QoL and the impact of the disease on the caregivers were assessed using the following methods: UHDRS Functional Assessment Score, SF-36 Scale and Caregiver Burden Inventory. Multiple regression analysis showed that motor disturbances, cognitive impairment, apathy and disease duration were the independent predictors of disability. Depression and cognitive disturbances were the determinants of patient's QoL, while motor disturbances and depression were the predictors of the caregiver burden. Patient's disability and QoL as well as caregivers' burden should be taken into consideration while planning treatment strategy and the results of the present study show that the predictors of those treatment targets are different.