BACKGROUND: Depression is very prevalent amongst myocardial infarction (MI) patients. It has been reported to be associated with adverse clinical events in these patients. The purpose of this study was to consider the relationship between personal control at baseline and the onset of post-MI depression. METHODS: A total number of 176 MI patients aged 32-84 years old who were admitted to coronary care units (CCUs) in Isfahan, Iran were selected. Baseline data was collected by a demographic and medical questionnaire, personal control scale, Beck Depression Inventory and echocardiography. Beck Depression Inventory for Primary Care was completed by the subjects 3 months after discharge. Covariance model was used to analyze the data. RESULTS: The findings indicated that 45% of the participants suffered from post-MI depression. Analysis of covariance showed a significant difference between patients with and without post-MI depression in personal control scores (F = 6.16; P < 0.05). CONCLUSION: Generally, our findings suggested relationship between patients' beliefs about having control over the disease and the onset of post-MI depression. This finding can be considered in rehabilitation courses to prevent post-MI depression.         Keywords: Myocardial Infarction, Depression, Personal.