Objective :To explore influence of intra—arterial thrombolysis combined hyperbaric oxygen on serum levels of soluble intercellular adhesion molecule—1 (sICAM—1) and calcitonin gene related peptide (CGRP) in patients with severe ischemic stroke .Methods : A total of 96 patients with severe ischemic stroke in our hospital were randomly and equally divided into thrombolysis group and combined treatment group (received intra—arterial thrombolysis +hyperbaric oxygen therapy ).United States National Institutes of Health Stroke score (NIHSS) was used to assess neurological function recovery , and modified Rankin rating score (mRS) was used to assess recovery of clinical symptoms.After two—week treatment ,clinical therapeutic effect etc .were compared between two groups .Results :Compared with thrombolysis group after treatment ,there was significant rise in total effective rate (77.08% vs. 93. 75%, P＝0.021) ;significant reductions in scores of NIHSS [ (8.10 ± 3.45) scores vs .(5.36 ± 2.11) scores] and mRS [ (2.58 ± 0. 80) scores vs .(1.81 ± 0.76) scores] ;significant reduction in serum sICAM—1 level [ (237.31 ± 18. 04) ng／ml vs.(220.25 ± 16.40) ng／ml] ,and significant rise in serum CGRP level [ (27.02 ± 6.06) pg／ml vs. (35.24 ± 6.13) pg／ml] in combined treatment group , P＝0.001 all.There was no significant difference in revascu—larization within two weeks between two groups , P＝0.551. Conclusion : Intra—arterial thrombolysis combined hy—perbaric oxygen possesses significant therapeutic effect on patients with severe ischemic stroke .It can relieve clinical symptoms ,recover cognitive function ,improve revascularization rate in these patients .