Objective To explore the risk factors of poor prognosis of anterior circulation acute ischemic stroke with large-vessel occlusion (AIS-LVO) patients after endovascular therapy (EVT), so as to determine the predictive value of D-dimer for poor prognosis of anterior circulation AIS-LVO patients after EVT. Methods Anterior circulation AIS-LVO patients who received EVT and hospitalized in the Department of Neurology, Hebei General Hospital from Dec. 2018 to Dec. 2022 were enrolled. According to the 90-d modified Rankin scale (mRS) score after operation, they were assigned to good prognosis group (mRS score of 0-2) or poor prognosis group (mRS score of 3-6). Preoperative Alberta Stroke Program early computed tomography score (ASPECTS), preoperative National Institutes of Health stroke scale (NIHSS) score, preoperative Glasgow coma scale score, immediate postoperative modified thrombolysis in cerebral infarction (mTICI) grade, general data, and laboratory data of anterior circulation AIS-LVO patients were collected. Binary logistic regression was used to analyze the influencing factors of poor prognosis in anterior circulation AIS-LVO patients after EVT, and receiver operating characteristic (ROC) curve was used to evaluate the predictive value of D-dimer for poor prognosis. Results A total of 143 patients with anterior circulation AIS-LVO undergoing EVT were enrolled, with 54 patients in the poor prognosis group and 89 in the good prognosis group. Compared with the poor prognosis group, patients in the good prognosis group had younger age, lower proportion of diabetes mellitus, lower preoperative NIHSS score, higher preoperative ASPECTS and Glasgow coma scale score,higher proportion of immediate postoperative mTICI grade 2b-3, and lower preoperative D-dimer level (all P＜0.05). Binary logistic regression analysis showed that preoperative NIHSS score (odds ratio[OR］＝1.096, 95% confidence interval[CI］ 1.007-1.193), immediate postoperative mTICI grading (OR=19.609, 95% CI 5.354-71.815) and preoperative D-dimer level (OR=1.310, 95% CI 1.128-1.521) were independent risk factors for poor prognosis in anterior circulation AIS-LVO patients receiving EVT. The area under the ROC curve value of D-dimer for the the poor prognosis of anterior circulation AIS-LVO patients after EVT was 0.642 (95% CI 0.54-0.745). Conclusion Preoperative NIHSS score, immediate postoperative mTICI grading and higher preoperative D-dimer level are independent risk factors for poor prognosis in anterior circulation AIS-LVO patients after EVT. AIS-LVO patients with elevated D-dimer levels before surgery may have a poor prognosis after EVT.