Background Although researchers have shown that prodromal symptoms can predict acute coronary events, the ability of patients with acute coronary syndrome (ACS) to identify these symptoms in a timely manner is limited. Objectives We aimed to assess prodromal symptoms in Chinese patients with ACS and their responses to symptoms by sex. Design This cross-sectional, multicenter study involved 5 teaching hospitals in China and included 806 patients admitted for ACS between June 2013 and February 2014. The McSweeney Acute and Prodromal Myocardial Infarction Symptom Survey (Chinese version) was used to gather data. Results Among 806 patients (including 483 women), 688 (85.4%) experienced at least 1 prodromal symptom before ACS onset. Using adjusted logistic regression models, we determined that women were significantly more likely than men to report back pain, between- or under-shoulder blade pain/discomfort, sleep disturbances, anxiousness, or heart racing. The prevalence of generalized chest pain and loss of appetite was higher among men than women. Only 41% of patients attributed their prodromal symptoms to the heart, and women were more likely than men to attribute prodromal symptoms to a heart attack. Conclusions More than two-thirds of patients with ACS reported at least 1 prodromal symptom, with some significant sex differences. Most patients do not attribute their symptoms to an impending ACS event.