The current endovascular treatment has increased the recanalization rate to more than 90%. Even so, the prognosis rate of stroke is still less than 50%. Our previous research confirmed that the neuroprotective effect of Normobaric Hyperoxia (NBO) from multiple perspectives. However, the clinical study on NBO was not satisfactory, which might be due to the absence of vascular recanalization therapy. Therefore, The investigators conducted this RCT study to further explore the Efficacy and safety of NBO combined with endovascular treatment in patients with acute ischemic stroke.