BACKGROUND/AIMS: The differences in the clinical course of Crohn's disease (CD) and ulcerative colitis (UC) among Asian countries remain unknown. Thus, we compared the clinical characteristics, treatment, and one-year outcomes of newly diagnosed inflammatory bowel disease (IBD) patients between Vietnam and Korea. METHODS: A retrospective cohort study was conducted at seven tertiary hospitals in these countries between January 2020 and January 2021. Data on demographics, diseases, treatment, and outcomes during 1 year after diagnosis were collected. RESULTS: Among 225 patients (60 from Vietnam and 165 from Korea), 140 and 85 were diagnosed with UC and CD, respectively. Severe activity ( CONCLUSIONS: Although Vietnamese IBD patients had higher baseline clinical and phenotypic severity than their Korean counterparts, no significant differences in short-term outcomes were observed, potentially reflecting the impact of the higher rate and early biologic usage in Vietnamese patients.