en Aim: Diabetes mellitus (DM) is a life time disease that requires change in patients' self-care and life style. The aim of this study was to determine the effects of predisposing, reinforcing and enabling factors on the self-care of patients with DM in Ardabil City, Iran in 2016.<br />Methods: This quasi-experimental study was conducted on 129 patients with DM referred to the diabetic centers of Ardabil. We used the components of PRECEDE model for planning the program. The educational program was executed on six information sessions. Changes in the predisposing, reinforcing, enabling factors and self-care behaviors one month after the intervention activities were assessed by using the same questionnaire. Data were analyzed through SPSS 16 software using descriptive and analytical tests.<br />Findings: The mean age of the patients was 56.82(±13.4) years, 69.8% of them were married and 20.2% were illiterate. According to the results, the mean scores for the knowledge, attitude, self-efficiency, self-care behavior, and reinforcement factors increased significantly after the educational intervention (p-value >0.001).<br />Conclusion: Educational intervention with PRECEDE-PROCEED model improved the diabetic patient’s self-care. Diabetes mellitus,Enabling factors,Predisposing factors,Reinforcing factors,Self-care behaviors 37 45 http://hehp.modares.ac.ir/browse.php?a_code=A-5-21639-1&slc_lang=en&sid=4