Background Traditional Chinese medicine (TCM) is used in the treatment of many conditions, including heart failure (HF), although it is not well characterized. Methods and Results We conducted a retrospective analysis of TCM use in a random sample of hospitalizations for HF within a random sample of Western medicine hospitals in China in 2015 using data from the China PEACE 5r-HF (China Patient-Centered Evaluative Assessment of Cardiac Events 5 Retrospective Heart Failure Study). We describe the frequency of TCM use and its association with patient characteristics, in-hospital use of evidence-based therapies, and hospital characteristics using hierarchical logistic regression models. Finally, we assessed risk-adjusted in-hospital bleeding and mortality. Among 10 004 patients hospitalized with HF (median age, 73 years; 48.9% women) from 189 hospitals, 74.7% received TCM (83.3% administered intravenously). The most commonly used agent was Salvia miltiorrhiza (51.2%). Patients with coronary artery disease (odds ratio [OR], 1.73; 95% CI, 1.53-1.95) or stroke (OR, 1.32; 95% CI, 1.15-1.51) were more likely to receive TCM; there was no correlation with evidence-based therapy use. Nearly all hospitals (99.4%) used TCM, with substantial variation across hospitals (median OR, 3.29; 95% CI, 2.82-3.76). In-patient bleeding (OR, 1.39; 95% CI, 1.03-1.88) and mortality (OR, 1.36; 95% CI, 1.04-1.79) were higher with Salvia miltiorrhiza, although not with other TCMs. Conclusions In a nationally representative sample of patients hospitalized with acute HF in China, three fourths received TCM. Nearly all hospitals used TCM, although use varied substantially by hospital. Although TCM was not used in lieu of evidence-based therapies for HF, we found a signal for harm with the most commonly used TCM. Clinical Trial Registration URL: https://www.clinicaltrials.gov. Unique identifier: NCT02877914.