BACKGROUNDAcute ischemic stroke (AIS) is mainly caused by cerebral blood flow disorders, which further leads to ischemic brain necrosis or encephalomalacia. The role of homocysteine (Hcy), an independent risk factor for cardiovascular disease, in the development of atherosclerosis is gradually revealed. However, studies are still rare and little is known about the relationship of Hcy level with the prognosis.AIMTo explore the relationship between Hcy level and prognosis in elderly patients with AIS after thrombolytic therapy with recombinant tissue plasminogen activator (rtPA).METHODSA total of 120 patients with acute ischemic stroke who were admitted to Jingzhou Central Hospital and underwent recombinant tissue plasminogen activator treatment were randomly selected from January 2017 to December 2018. They were divided into two groups according to the level of Hcy, with 60 patients in each group. Patients with Hcy ≥ 18.54 umol/L were included into a high-level group and those with Hcy < 18.54 umol/L were included into a low-level group. The outcomes were analyzed in the two groups after the treatment.RESULTSThe National institute of Health Stroke Scale (NIHSS) scores were significantly higher in the high-level group than in the low-level group before and 1 h after the treatment (P < 0.05). There was no significant difference in NIHSS scores between the two groups at 12 and 24 h after the treatment (P > 0.05). The Modified Rankin scale (MRS) scores were significantly higher in the high-level group than in the low-level group before and 1 h after the treatment (P < 0.05). There was no significant difference in MRS scores between the two groups at 12 and 24 h after the treatment (P > 0.05). NIHSS and MRS scores were positively correlated with the prognosis after thrombolytic therapy (P < 0.05).CONCLUSIONThe level of Hcy is closely related to the prognosis of elderly patients with acute ischemic stroke, and after rtPA treatment, the prognosis of elderly patients is improved significantly.