Objective The present study was done with the objective of assessing the self-care practices among diagnosed type 2 diabetes mellitus patients in hospital of Islamic Azad University of Medical Sciences in Tehran, Iran. Methods In this cross-sectional study, 314 Iranian patients older than 18 years of age with type 2 diabetes were completed Diabetes Self-Management Questionnaire. Data was analyzed by ANOVA, t-test, correlation and liner regression. Results A significant association was found between the diabetes self-management sum scale and body mass index, Dietary control subscale and body mass index, Physical activity subscale and body mass index & job and Healthcare use subscale and diabetes treatment (p<0.05). Conclusion Due to the high BMI in respondents, Overweight and obese respondents need to be advised by health professionals on physical activities and proper diet to achieve healthy weights to avoid complications related to diabetes mellitus. Keywords Diabetes self-management, Type 2 diabetes, Diabetes Self-Management Questionnaire DOI: 10.7176/JMPB/63-02 Publication date: January 31st 202