Background and purposeStroke is the leading cause of mortality and disability in China. Precise aetiological classification, imaging and biological markers may predict the prognosis of stroke. The Third China National Stroke Registry (CNSR-III), a nationwide registry of ischaemic stroke or transient ischaemic attack (TIA) in China based on aetiology, imaging and biology markers, will be considered to clarify the pathogenesis and prognostic factors of ischaemic stroke.MethodsBetween August 2015 and March 2018, the CNSR-III recruited consecutive patients with ischaemic stroke or TIA from 201 hospitals that cover 22 provinces and four municipalities in China. Clinical data were collected prospectively using an electronic data capture system by face-to-face interviews. Patients were followed for clinical outcomes at 3 months, 6 months and 1–5 year annually. Brain imaging, including brain MRI and CT, were completed at baseline. Blood samples were collected and biomarkers were tested at baseline.ResultsA total of 15 166 stroke patients were enrolled, among which 31.7% patients were women with the average age of 62.2±11.3 years. Ischaemic stroke was predominant (93.3%, n=14 146) and 1020 (6.7%) TIAs were enrolled.ConclusionsCNSR-III is a large scale nationwide registry in China. Data from this prospective registry may provide opportunity to evaluate imaging and biomarker prognostic determinants of stroke.