Background: It is widely recognized that expenditures for medical treatment, rehabilitation services, and assistive devices for families with children with disabilities place a significant financial burden on household budgets, often making it difficult to meet basic daily needs. In recent years, extensive research has been conducted in countries with well-developed economic and social service systems to examine how disability affects family financial stability. Additionally, there is growing evidence on the relationship between financial burden and quality of life among families raising children with disabilities. Aim: To determine the correlation between financial strain and family quality of life (FQOL) among families raising children with disabilities. Materials and Methods: A cross-sectional study was conducted between 2024 and 2025, involving 735 caregivers from both urban (Ulaanbaatar) and rural areas, recruited through governmental and non-governmental organizations. Data were collected using measures of average household income, the proportion of household income spent on disability-related expenses, self-reported financial burden, and the standardized Family Quality of Life questionnaire developed by Hoffman (2006), which includes five domains. Descriptive statistics and linear regression analyses were performed. Result: The average household income of participants was 2,905,277.16±2,141,515.84 MNT. Families with children diagnosed with epilepsy, intellectual disabilities, cerebral palsy, and autism spectrum disorders spent a higher proportion of their annual income on related expenses. Each unit increase in the frequency of financial burden was associated with a 0.22-point decrease in overall family quality of life (p<0.001). Furthermore, a one-unit increase in the proportion of household income spent on child-related treatment and services was associated with a decrease in physical and material well-being by 0.007 points (p<0.001) and overall family quality of life by 0.003 points (p=0.037). Conversely, a 100,000 MNT increase in household income was associated with an increase in family quality of life scores (B=0.00249; p<0.001). Conclusion Household income and the proportion of income spent on disability-related expenses are significant factors influencing quality of life. Financial stress experienced by families with children with disabilities negatively affects family quality of life.