The present study based on World Health Organization quality of life (WHOQOL-BREF) scale to examine quality of life of the caregivers caring for their children/adolescents with intellectual disabilities in Taiwan, and the factors contributing to their quality of life. Structured interviews were conducted with 597 caregivers of children/adolescents with intellectual disabilities. The results found that the mean scores in each domain of WHOQOL-BREF of the caregivers as the followings: physical capacity (PC) was 13.71±2.35, psychological well-being (PW) was 12.21±2.55, social relationship (SR) was 12.99±2.43 and environment (EN) was 12.32±2.38. These mean scores were lower than the general population and slight higher than the caregivers of adults with intellectual disabilities in Taiwan. Finally, multiple stepwise regressions were conducted to examine the characteristics of caregiver and children/adolescents with intellectual disabilities will more likely explained the WHOQOL-BREF mean scores. The study found the following three factors: self-perceived health status, household income and stress from insufficient family support were significantly correlated to all four domains in multiple stepwise regression analyses. The results highlights that caregivers of children and adolescents with intellectual disabilities seem to display a lower WHOQOL-BREF mean score than the general population, probably for a combination of stress, health and household income factors. These finding must be taken into account in policy making to provide better and more specific supports and interventions for the caregivers of people with intellectual disabilities.