Aim Myocardial infarction (MI) affects the working-age group and cause many absences and lost days of work. Some occupational factors effect in the prognosis of MI patients. The objective of this study was to determine predictors of early, late and no return to work (RTW) after MI.Material and methods In this cohort study, 240 pre-employed, male patients with MI from April 2020 through February 2022 provided data about their demographic, occupational, psychosocial, and medical information. Data was also collected about the treatment they received as patients, their feelings about socioeconomic support, and RTW time. RTW within two weeks after MI was defined as early RTW. The relationships of these variables and with early RTW and with late or no RTW were analyzed.Results Ninety-four patients (39.6 %) returned to work within two weeks after MI, whereas 207 patients (87.3 %) returned to work by the end of six months. Many variables, including coworker support, were associated with early RTW in a univariate analysis. Regression analysis revealed that age, coworker support, marital status, the patient's own estimated RTW time, the number of the vessels with occlusion, and comorbidity were predictors of early RTW. Of these factors, only coworker support would be subject to modification.Conclusions This study indicates that improving support from coworkers can increase early RTW after MI.