•Identification of a dietary pattern associated with an elevated risk of diabetes in Korean adults, characterized by high consumption of refined white rice, kimchi, salted vegetables, wheat flour, and bread, coupled with low intake of whole grains, legumes with tofu and soymilk, poultry, eggs, and plant oils.•This study demonstrated the construct validity of the identified dietary pattern in two independent studies, underscoring its utility in assessing the diabetic potential of overall diets.•An association between higher scores of the identified dietary pattern and increased diabetes risk was observed, emphasizing the consistency and robustness of the findings. The aim of this study was to identify dietary patterns associated with diabetes in Korean adults and to investigate their association with diabetes risk in both a cross-sectional and prospective study. Predefined food groups collected by the Korea National Health and Nutrition Examination Survey (KNHANES 2015–2018, n = 19 721) were entered in a reduced rank regression (RRR) model, followed by stepwise linear regression analyses to identify the most predictive dietary patterns. We evaluated the construct validity of dietary patterns in two independent samples from KNHANES 2019 to 2021 (n = 14 223) and the Health Examinees (HEXA) cohort study (n = 30 013). Associations between dietary patterns and diabetes risk were examined using multivariable regression and multivariable-adjusted Cox proportional hazard models, respectively. A dietary pattern was identified with high positive loadings for refined white rice, kimchi and salted vegetables, wheat flour and bread, and seasonings, and high negative loadings for whole grains, legumes with tofu and soymilk, poultry, eggs, and plant oils. The higher pattern scores were significantly associated with diabetes risk in KNHANES 2015 to 2018 (male: odds ratio OR: 1.59; 95% confidence interval CI: 1.35, 1.88; female: OR: 1.37; 95% CI: 1.18, 1.52), KNHANES 2019 to 2021 (male: OR: 1.47; 95% CI: 1.01, 1.69; female: OR: 1.37; 95% CI: 1.18, 1.54), and HEXA study (male: hazard ratio HR: 1.10; 95% CI: 1.01, 1.34; female: HR: 1.24; 95% CI: 1.02, 1.52). Dietary patterns derived by RRR followed by stepwise linear regression analyses were associated with increased risks of diabetes among Korean adults.