To compare the clinical efficacy of stent thrombectomy and arterial thrombolysis in the treatment of acute middle cerebral artery occlusion of more than 4.5 hours. Methods：Ninety-nine patients with acute middle cerebral artery occlusion were divided into the thrombolytic group (n=41) and the thrombectomy group (n=58) according to treatment method. Selective intra-arterial thrombolysis was performed on thrombolysis group patients, and mechanical thrombectomy using the Solitaire stent was performed on thrombectomy group patients. Thrombolysis in Cerebral Infarction (TICI) was used to evaluate the recanalization of vessels prior to the conclusion of surgery, and the operation time of the two groups was compared. The recovery of the two groups was evaluated by the National Institutes of Health Stroke Scale (NIHSS) score. Adverse reactions were recorded and followed up at 90 days. Results：The recanalization rate and complete recanalization rate of the thrombectomy group were significantly higher than those of thrombolysis group (94.8% v.s. 78.0, 67.2% v.s. 41.5%, both P<0.05). The operation time of the thrombectomy group was lower than that of the thrombolysis group (P<0.05). After treatment, the NIHSS score of the thrombectomy group was significantly better than that of the thrombolysis group (P<0.05). The total effective rate of the thrombectomy group was 96.6%, which was significantly higher than the 87.8% rate of the thrombolysis group (P<0.05). The cure rate of the thrombectomy group was significantly higher than that of the thrombolysis group (50.0% v.s. 31.7% , P< 0.05). The patients in the thrombolysis group had a higher rate of intracranial hemorrhage than those in the thrombectomy group (P<0.05). At the 90-day follow-up, patients in the thrombectomy group showed better recovery than those in the thrombolysis group (P<0.05). Conclusion：Stent thrombectomy can significantly improve the clinical prognosis of patients with cerebral arterial embolization of over 4.5 hours