Abstract Background: Diabetes is a serious problem and self- management is effective factor for diabetes control. Personality trait is one of the important factors in diabetes self- management. In this study, purpose was determination of effective personality traits in self- management. Material and Methods: In this cross sectional study, data were collected from a convenience sample of 396 diabetic patients, using self- management and Big five personality Scales. For data analysis, multiple linear regression models were used. Results: Among five personality traits, the most effective traits in self- management were conscientiousness, openness, and extraversion (R2= 32%). Conscientiousness and openness were significant predictors for all of self- management aspects. Extraversion was effective factors in self- regulation, self- integration, and following treatment. Conclusion: The education for diabetic patients with neuroticism and agreeableness traits is necessary and Patients with conscientiousness, openness, and extraversion traits can be used as model in educational process.