Hypertrophic cardiomyopathy (HCM) is associated with poor prognosis. It has been reported that there is no difference in in-hospital mortality after acute myocardial infarction (AMI) between patients with and without HCM. However, whether there are differences in long-term outcomes after AMI between patients with and without HCM remains unclear. In this study, we analyzed the clinical profiles of 78 consecutive patients with HCM and AMI (HCM and AMI group), 78 sex- and age-matched patients with AMI and without HCM (AMI group), and 78 sex- and age-matched patients with HCM and without AMI (HCM group). The study end points were major adverse cardiac events (MACEs) and secondary end points. During the follow-up period of 4.8 ± 3.6 years, MACEs occurred in 19 (27.9) patients in the HCM and AMI group, in 11 (16.7%) patients in the AMI group, and in 8 (12.3%) patients in the HCM group. The long-term outcomes of the HCM and AMI group were inferior to that of the other 2 groups (log-rank P = .030 for MACEs, log-rank P = .032 for secondary end points). In conclusion, patients with AMI with HCM exhibited worse long-term outcomes than did patients with AMI without HCM and patients with HCM without AMI.