Abstract South Korea has experienced significant immigrant growth, with international marriages playing a key role in this demographic change. In 2019, international marriages accounted for 10.3% of all marriages, increasing the number of multicultural households. Multicultural families in Korea faced controversies over accepting new members in a society traditionally considered racially and ethnically homogenous. In rural areas, where patriarchal and conservative values prevail, there is greater discrimination and negative perception towards foreigners compared to urban areas, impacting access to healthcare. This potentially adversely affects the health of married immigrants. However, research on this issue is limited. This study aims to examine the differences in health behaviors, access to care, and health status between multicultural and non-multicultural families in rural and urban areas. Using a cross-sectional study design based on the 2023 Community Health Survey, the sample included 228,216 adults from non-multicultural families and 3,373 adults from multicultural families. Adjusted differences in outcome were estimated using regression models, including linear probability and logistic models. Overall, there were minimal or no differences in health behaviors and health status between adults from multicultural and non-multicultural families. However, significant differences were observed in access to care, such as annual health check-ups (0.72 [0.64, 0.81]) and vaccinations (0.84 [0.76, 0.94]). Non-multicultural families showed regional differences in all outcomes, whereas multicultural families exhibited minimal or no regional differences. These findings suggest that multicultural families may face barriers beyond regional environments, limiting their access to care and potentially leading to long-term negative health outcomes. Targeted policy development for multicultural families in Korea is necessary to address this issue. Key messages • Access to health care may vary for individual and local factors, especially for people with different ethnicities or cultures. • Multicultural families may encounter greater barriers than individual and regional characteristics, requiring the development of tailored policies for immigrants and multicultural families.