Objective: The aim of the study was to investigate the association between depression and maintenance of smoking cessation at 1-year follow-up in patients admitted with first-incidence acute myocardial infarction (MI) with a focus on educational level. Methods: From the 1st of September 2002 to the 31st of December 2004, 388 patients < 75 years old were admitted at Aarhus University Hospital in Denmark with first-incidence MI. The patients were screened for depression 6 weeks after admission and offered cardiac rehabilitation (CR). Patients were included if they stopped smoking at admission or in the next 6 weeks, if they were screened for depression and if they gave information concerning smoking status. Results: A quarter of the patients were screened positive for depression. There was no significant difference in the participation at the smoking cessation part of the rehabilitation for patients screened positive or negative for depression, whether the results were adjusted for gender and educational level (OR = 0.84; p-value = .75) or not (OR = 0.75; p-value = .56). There was a significant association between a positive depression screening and failing to maintain a smoking cessation in men (OR = 7.67; p-value = .03) at 1-year follow-up. When adjusted for educational level a significant association was still seen (OR = 7.48; p-value = .01). Conclusions: There was a significant association between a positive depression screening and failing to maintain a smoking cessation in men at 1-year follow-up. The result was consistent after adjusting for educational level.