Background and Objectives: Type 2 diabetes has multifactorial causation, with obesity and metabolic dysregulation being two of them. Personality traits are also known to influence many metabolic processes and have been associated with the pathogenesis of diabetes as well as obesity. The objective of the study was to analyze the differences in the big five personality traits of normal-weight type 2 diabetes mellitus, obese type 2 diabetes mellitus patients, and healthy controls. Methods: A total of 70 subjects were included in the study after outpatient-based screening, of which 40 were type 2 diabetes patients (20 obese and 20 normal weight) and 30 were healthy controls. After the anthropometric screening, the personality assessment of the subjects was done using the Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness-Five Factor Inventory (NEO-FFI). The differences in the scores of each trait for every group were analyzed by analysis of variance (ANOVA) with Tukey’s honest significant difference (HSD) post hoc corrections. The difference in the scores between controls and diabetes patients was also compared by independent samples t -test. Results: The neuroticism score was significantly higher in both the normal-weight diabetes group ( P = 0.01) and obese diabetes group ( P = 0.02) as compared to the control group. All diabetes patients when compared with healthy controls had a significantly higher neuroticism score ( P = 0.00) while their score of openness was significantly lower ( P = 0.035) than healthy controls. Interpretation and Conclusion: This study identifies the association of personality with type 2 diabetes mellitus. The diabetes patients have higher neuroticism and lesser openness to experience as traits of personality. Importantly, this association is present irrespective of the obesity status of the patients.