Background: A great number of people who have survived after stressful events experience positive psychological changes. These positive changes are recognized as posttraumatic growth. Objectives: The purpose of the current study was to examine the relationship between posttraumatic growth and meaning in life in patients with myocardial infarction. Methods: This is a descriptive correlational study conducted on 191 patients referring to the largest cardiology center (Bu-Ali Sina) in Qazvin, Iran. The sample was selected through a convenience sampling method based on the inclusion criteria. The data were collected using a demographic questionnaire, the posttraumatic growth inventory, and the meaning in life questionnaire. Data were analyzed with descriptive analysis. Inferential statistics (Pearson's test) were used to evaluate the relationship between posttraumatic growth and meaning in life. Results: The sample included 49 (25.7%) women and 142 (74.3%) men with the mean age of 59.6 ± 1.2 years. The mean total score of posttraumatic growth was 64.6 ± 11.5 and the mean total score of meaning in life was 49 ± 6.04. Based on the results, there was a significant positive correlation between posttraumatic growth and meaning in life (r = 0.71, P < 0.001). Conclusions: The occurrence of myocardial infarction can lead to some positive psychological changes called posttraumatic growth. Nurses, informal caregivers, and policymakers can use these findings to help patients cope with challenging conditions after myocardial infarction.