Background and Purpose-Low estimated glomerular filtration rate (eGFR) is known to be associated with clinical adverse outcomes. However, whether diabetes mellitus influences the association between eGFR and prognosis of stroke is still not elucidated. Methods-Prospective cohort of 17 280 (nondiabetic 12 498 and diabetic 4782) Chinese patients with acute stroke from the China National Stroke Registry and from abnormal glucose regulation in patients with acute stroke across China (ACROSS) between 2007 and 2009 were followed-up for 1 year for all-cause mortality, stroke recurrence, and stroke disability related to baseline eGFR in the presence and absence of diabetes mellitus. Results-Among nondiabetic patients, as compared with eGFR of 90 to 119 mL/min per 1.73 m(2), the adjusted odds ratio of lower eGFR of < 45 mL/min per 1.73 m(2) was 2.79 (95% confidence interval, 2.09-3.73) for all-cause mortality, 2.28 (1.74-2.98) for stroke recurrence, and 1.53 (1.16-2.01) for stroke disability; higher eGFR of >= 120 mL/min per 1.73 m(2) was just significantly associated with higher risk of all-cause mortality (odds ratio, 1.38; 95% confidence interval, 1.02-1.86) but not with other outcomes. In diabetic patients, the adjusted odds ratios of all-cause mortality, stroke recurrence, and stroke disability in lower eGFR were 2.16 (1.51-3.08), 1.43 (1.02-2.00), and 1.38 (0.98-1.95), respectively; higher eGFR was significantly associated with higher risks of all stroke outcomes. Conclusions-Decreased eGFR (<45 mL/min per 1.73 m(2)) is a strong predictor of all-cause mortality, stroke recurrence, and stroke disability in diabetic and nondiabetic patients with acute stroke. Increased eGFR (>= 120 mL/min per 1.73 m(2)) is associated with all of stroke outcomes in diabetic patients and linked to all-cause mortality in nondiabetic patients.