This study examines the operational status and effectiveness of the Language Development Support Program for children from multicultural families and evaluates its outcomes. Using annual program reports from Family Centers, this study analyzed five-year trends in program operation and compared regional patterns of service provision. In addition, a nationwide survey of 182 Family Centers was conducted, and in-depth interviews were carried out with seven program practitioners to examine qualitative outcomes. The findings indicate that service provision, which temporarily declined during the COVID-19 pandemic, recovered rapidly and has since remained stable. Program operation was relatively consistent across regions, suggesting equitable access to services nationwide. The majority of beneficiaries were preschool-aged children who received sustained, long-term intervention. The program improved children’s language abilities and contributed to positive changes in overall family functioning. Overall, the results suggest that the program functions as an early intervention service that supports language development among children from multicultural families. The study confirmed that the program contributes directly to children’s holistic development and indirectly to the social adaptation and integration of multicultural families.