Objective: This study evaluates reocclusion prognostic outcomes and explores reocclusion risk factors after mechanical thrombectomy (MT) in Chinese stroke patients. Methods: Altogether, 614 patients with AIS with successful recanalization after MT were recruited in this study and divided into the reocclusion and the non-reocclusion group depending on the 24-h imaging results after MT. Differences between the two groups were compared including 24-h and 7-day National Institutes of Health Stroke Scale (NIHSS) scores, 90-day modified Rankin scale(mRS) scores, good prognosis (mRS:0–2) rates, incidence of intracranial hemorrhage, and 90-day mortality. Results: Forty-four (7.2%) patients experienced reocclusion within 24 h. Compared with the non-reocclusion group, patients in the reocclusion group had higher 24-h (15 vs. 13) and 7-day (15 vs. 9) NIHSS scores, 90-day mRS scores (4 vs. 3), and 90-day mortality rates (34.1% vs. 18.6%); lower rates of good prognosis (13.6% vs. 9.3%); and a higher incidence of early neurological deterioration (36.4% vs. 14.7%). Age, internal carotid artery occlusion (ICA), intravenous thrombolysis (IVT), number of thrombectomy passes, stent implantation, and levels of D-dimer (adjusted odds ratio and 95% confidence interval: 0.97, 0.94–0.99; 2.40, 1.10–5.23; 2.21, 1.05–4.66; 2.60, 1.04–6.47; 0.25, 0.09–0.67; and 1.06, 1.01–1.12, respectively) were independently associated with 24-h reocclusion. Interpretation: The prognosis of reocclusion after MT was poor. Timely evaluation of these factors including age, D-dimer, ICA occlusion, IVT, number of passes, and stent implantation and appropriate intervention could reduce the incidence of reocclusion for Chinese stroke patients. © 2020 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals, Inc on behalf of American Neurological Association.