Objective To evaluate the efficacy of endovascular therapy in patients with progressive ischemic stroke beyond time window under the guidance of multimodal computed tomography （CT）. Methods From October 2021 to October 2023， 412 patients with acute progressive anterior circulation ischemic stroke and onset time of more than 8 hours in Department of Neurology of Yuebei People's Hospital were selected as participants. All selected patients underwent multimodal CT evaluation， and there was a mismatch between the low perfusion area and the core infarction area， with a ratio greater than 1.8. The patients were divided into a study group （cerebral vascular intervention treatment group） and a control group （conservative treatment group） based on whether they received interventional treatment for cerebrovascular disease. Chi square test was used to evaluate the incidence of symptomatic cerebral hemorrhage， severe complications， and mortality in two groups of patients. Repeated measures analysis of variance and independent sample t-test were used to analyze the National Institute of Health Stroke Scale （NIHSS） scores， modified Rankin Scale （mRS） scores， Barthel Index （BI） scores at 90 days after treatment， and good prognosis rate of two groups of patients before and after treatment. The surgical efficacy and risks of study group were also evaluated. Results After excluding 24 patients with failed vessel reperfusion or postoperative vessel occlusion， a total of 388 patients were included， including 134 in study group and 254 in control group. The vascular recanalization rate of study group was 85.0% （134/158）， and the incidence of surgical complications including arterial dissection， vascular rupture， and ectopic embolism was 6.72%（9/134）. In study group， the incidence of severe pneumonia was 23.88%（32/134）， which was lower than the 35.04%（89/254） in control group， and the tracheotomy rate was 8.96%（12/134）， lower than the control group's 16.93%（43/254）， and the incidence of symptomatic cerebral hemorrhage was 9.70%（13/134）， which was higher than the control group's 1.57%（4/254）， and the incidence of cerebral herniation and large area cerebral infarction was 31.34%（42/134）， which was lower than the 59.84% （152/254） in control group， and the above differences were statistically significant （all P ＜ 0.05）. The rate of automatic discharge and death of study group was 8.21%（11/134）， which was lower than the 15.35%（39/254） of control group， and the difference was statistically significant （P＜ 0.05）. The NIHSS scores of study group at 24 hours， two weeks， and 90 days were （10.51±3.27）， （8.57±1.39）， （5.39±1.32）， respectively， all lower than those of control group （19.57±1.35）， （12.30±2.35）， and （9.39±2.37）， and the differences were statistically significant （P＜ 0.05）. After 90 days of treatment， the mRS score of study group was （1.54±0.46）， which was lower than that of control group （3.19±0.57）， and the difference was statistically significant （P ＜ 0.05）. The BI score of study group was （71.56±12.43）， which was higher than that of control group （57.23±10.37）， and the difference was statistically significant （P ＜ 0.05）. The good prognosis （mRS ≤ 2） rate of study group after 90 days was 38.81%（52/134）， which was higher than control group's 27.17%（69/254）， and the difference was statistically significant （χ2 =5.539，P＜ 0.05）. Conclusions Under the guidance of multimodal CT， there is a certain risk of symptomatic cerebral hemorrhage in patients with acute progressive anterior circulation ischemic stroke beyond time window undergoing endovascular therapy. However， timely blood vessel reperfusion under the guidance of multimodal CT can reduce the poor prognosis and mortality of patients， alleviate neurological deficits， improve activities of daily living and prognosis.