Objective:To investigate the value of net water uptake (NWU) for predicting early neurological improvement (ENI) after endovascular treatment in patients with acute anterior circulation large vessel occlusion stroke.Methods:A case-control study. A total of 132 patients (80 men, 52 women, median age 68 years) with acute anterior circulation large vessel occlusive stroke receiving endovascular treatment were retrospectively analyzed at Jinling Hospital from October 2014 to September 2019. Patients were divided into two groups based on the occurrence of ENI, which was defined as either an improvement of NIHSS score of ≥4 points, or an NIHSS score of 0 or 1 at 24 hours after endovascular treatment. The rank sum test, Chi square test, and other methods were used to compare differences in baseline characteristics between the two groups. Logistic regression analysis was used to investigate independent predictors of postoperative ENI. Receiver operating characteristic curve analysis used to assess the capacity of NWU to predict ENI.Results:Of the 132 patients in the study, ENI occurred in 47 and did not occur in 85. In multivariate logistic regression analysis age [odds ratio ( OR)=0.940, 95% confidence interval ( CI) 0.903-0.979, P=0.003], time from stroke onset to puncture ( OR=0.995, 95% CI 0.991-0.999, P=0.025), time from puncture to recanalization/end of operation ( OR=0.985, 95% CI 0.974-0.996, P=0.007), NWU ( OR=0.762, 95% CI 0.620-0.937, P=0.010), and mTICI ( OR=1.644, 95% CI 1.043-2.590, P=0.032) were predictive factors for ENI. Receiver operating characteristic curve analysis indicated that NWU could effectively predict ENI (area under the curve=0.642, 95% CI 0.543-0.741, P=0.007), and prediction accuracy was improved when it was combined with other clinical parameters. Conclusion:NWU is an independent predictor of ENI in patients with acute anterior circulation large vessel occlusive stroke undergoing endovascular treatment.