Mongolian immigration into South Korea has increased rapidly over the last decade. It is important to better understand dietary patterns of immigrants because these patterns are associated with health risk. This study aimed to characterize dietary patterns of Mongolian immigrants in South Korea. Dietary intakes of 500 Mongolian adults living in South Korea were assessed using the interviewer-administered 24-h dietary recall method. By cluster analysis, three dietary patterns were identified: “Mongolian” (26 %), “Transitional” (43 %) and “Korean” (31 %). The “Korean” pattern had a favorable food intake profile, with higher intakes of healthy foods, while the other patterns had features of an unhealthy diet. There were significant differences between the dietary patterns that were related to risk for chronic diseases. Overall, subjects following the “Korean” dietary pattern showed high adherence to World Health Organization recommendations for preventing diet-related chronic diseases, whereas the “Mongolian” and “Transitional” patterns showed low compliance. The results suggest the need for education programs targeting Mongolian immigrants who retain traditional dietary habits, to enhance their healthy food choices.