Objective: To investigate the relationship between the magnesium intake and patterns of diary and the risk of type 2 diabetes in Harbin residents. Methods: On April 2010, 24 communities in 7 districts of Harbin were selected as research sites using multi-stage stratified random cluster sampling method. A total of 9 734 residents aged 20-74 years was investigated using general questionnaire survey, dietary survey and biochemical indicators test. A total of 9 376 subjects were included in the study. Factor analysis was used to analyze dietary patterns. According to the quartile of dietary magnesium intake, the subjects were divided into four groups, from Q₁ to Q₄ group. The multivariate logistic regression model was used to analyze the relationship between dietary magnesium intake and the risk of type 2 diabetes within different dietary patterns. Results: A total of 998 subjects with type 2 diabetes were screened. The median age of the diabetic group and the non-diabetic group were 54.8 and 50.8, respectively, and the males accounted for 43.4% (2 896 cases) and 34.6% (433 cases), respectively. The magnesium intake median (P₂₅, P₇₅) of two groups was 336.36 (257.31, 440.65) and 339.50 (264.51, 443.78) mg/d. Four dietary patterns were identified as western dietary mode, savvy dietary mode, traditional dietary mode, and staple food mode. In the western dietary model, the Q₄ group had a higher risk of type 2 diabetes than Q₁ group, with an OR (95%CI) value of 1.56 (1.06 to 2.32). However, in the savvy diet mode, compared with the Q₁ group, the risk of diabetes in the Q₄ group was lower, and the OR (95%CI) value was 0.61 (0.37 to 0.96). There was no statistically significant association between dietary magnesium intake and the risk of type 2 diabetes without considering dietary patterns (P>0.05). Conclusion Dietary magnesium intake has a different relationship with the risk of type 2 diabetes within different dietary patterns.