BACKGROUND: Stroke is the leading cause of death in China. Despite the wide dissemination of evidence-based guidelines, data about adherence to these in routine clinical practice are scarce. We conducted a study using a nationwide registry to evaluate the implementation of evidence-based stroke performance indicators and associated guidelines, for patients with an ischemic stroke in China. METHODS AND RESULTS: The China National Stroke Registry is a prospective cohort study, including 12 416 patients diagnosed with acute ischemic stroke from 132 hospitals across China, for 1 year beginning September 2007. Twelve performance indicators were selected to evaluate the quality of stroke care. Multivariable Cox models were used to determine the association between optimal compliance and clinical outcomes. Conformity with performance measures ranged from a median of 6.5% for the use of intravenous tPA (tissue-type plasminogen activator) to 81.8% for early use of antithrombotics. The optimal compliance with all in-hospital measures was associated with 1-year death after admission (hazard ratio, 0.66; 95% CI, 0.55-0.79). The optimal compliance with all discharge measures was associated with the 1-year death after discharge (hazard ratio, 0.55; 95% CI, 0.44-0.69), 1-year stroke recurrence (hazard ratio, 0.81; 95% CI, 0.70-0.93), and favorable functional outcomes (defined as modified Rankin Scale score of <= 2) (hazard ratio, 1.10; 95% CI, 1.04-1.16). CONCLUSIONS: Adherence to evidence-based ischemic stroke care measures in China revealed substantial gaps, and select measures were associated with improved outcomes. These findings support the need for ongoing quality measurement and improvement in stroke care in China.