Background Women are more likely to delay medical help-seeking for ACS symptoms. Understanding patients’ experience of the symptoms and their response is essential in improving help-seeking behaviors and timely diagnosis and treatment for ACS. This study aimed to explore women’s experience of ACS, their response to the symptoms, and treatment-seeking decisions. Methods This qualitative descriptive study was conducted in a tertiary referral specialized heart hospital affiliated with Tabriz University of Medical Sciences, Iran. Participants included 39 women who had experienced ACS for the first time. Results Four main themes emerged from the analysis of interview transcripts: (1) the onset of symptoms, (2) the types of symptoms, (3) response to symptoms and (4) arriving at the hospital. These themes and associated sub-themes explained women’s experience of ACS symptoms, their response to the symptoms, and decision to seek medical help. Conclusions This study identified and discussed factors contributing to the prehospital delay in women and their decision-making to seek medical care for ACS symptoms. The results are consistent with previous research indicating that ACS symptoms in women are somewhat different from men, and women tend to underestimate their symptoms and attribute them to non-cardiac causes. Women should be supported to develop awareness and understanding of ACS symptoms and appreciate the importance of early treatment-seeking in the disease outcomes.