Background: Few studies have qualitatively explored their thoughts and actions after symptom onset to seek medical assistance in patients with acute myocardial infarction (AMI) in Korea. Objectives: This study was conducted to identify their decision-making behaviors during the period between onset of symptoms and treatment seeking, and to examine influencing factors on delayed presentation to hospital among patients with the first-time AMI. Methods: A total of 193 patients were conveniently recruited from a coronary care unit of C University hospital. After approval of institutional review board, semi-structured interviews were conducted focusing on their experience and interpretation of the episodes of AMI during their stays in the hospital following coronary intervention. The transcriptions were read repeatedly to identify the meaningful contextual nature of their decisions and actions. The qualitative data were also re-coded for quantitative analysis. Results: The median delay time was 12 hours (짹 107.9) and mean age of the sample was 63 짹 12.5 years (ranged 29-89). The majority (75%) did not recognize their symptoms as cardiac in origin and 61% thought their symptoms were not serious. The actions after symptom experience were: visiting a local clinic or hospital (49%); bearing and waiting to see if the symptoms would go away (23%); self-medication or visit pharmacy to have pills (21%); and contacting their family (17%). The reasons for delay were: no recognition of symptoms as serious; attribution to their weakened body strength or aging; and attribution to indigestion, severe flu or muscle pain. Logistic regression analysis showed that patients experienced symptoms as progressive or intermittent development, experienced symptoms at home, and not recognized as cardiac in origin or serious problem were significantly associated with delayed presentation > 12 hours (p< .05) when age, gender, and educational level were controlled for. Conclusions: This finding indicated a lack of knowledge about symptoms of AMI and appropriate decisions and actions to seek medical care when an AMI occurred. Public education should focus on the signs and symptoms of AMI and action guidelines following chest discomfort.