Predictors of quality of life in Chinese patients with acute coronary syndrome remain unknown. Between January 2006 and March 2009, a prospective cohort study of 782 patients with acute coronary syndrome was carried out, with follow-up 7 months later. Depression and anxiety symptoms were measured using the Hospital Anxiety and Depression Scale. Quality of life was assessed using the 36-Item Short-Form Health Survey. To identify predictors of decreased quality of life, both the physical and mental component summary scores were analyzed using multiple and ordinal logistic regression. In our quality-of-life model, diabetes mellitus was an independent risk factor for a low mental component summary score. Anxiety symptoms and the baseline mental component summary score were significant independent predictors of a low mental component summary score. Acute myocardial infarction was found to be a risk factor for a low physical component summary score. Anxiety symptoms, baseline physical component summary score, and systolic blood pressure on admission were significant independent predictive factors. Among patients with acute coronary syndrome, those with acute myocardial infarction, diabetes, or a low baseline quality of life need more care and effective intervention to improve their quality of life.