Abstract: Objective To observe the plasma homocysteine(Hcy) level of patients with cerebral infarction in order to investigate the relationship between homocysteine(Hcy) level and the incidence and prognosis of cerebral infarction,and provide the reference for the early monitoring and treatment of cerebral infarction. Methods Ninety-two cases of cerebral infarction patients were selected as the experiment group who were treated in the Civil Aviation General Hospital from January,2013 to January,2014,and 80 healthy volunteers were selected as the control group.There was no significant difference in the age and sex between the two groups.The plasma homocysteine(Hcy) levels of the two groups were compared.The patients in the experiment group were scored according to the degree of defect of the clinical neurological function.The plasma Hcy levels and prognosis of different defect degree were compared. Results The average plasma Hcy of the experimental group was (18.13±4.51) μmol/L,significantly higher than that of the control group(9.24±2.88) μmol/L(χ²=15.712,P=0.017),and the difference was statistically significant.The plasma Hcy in the experiment group of patients with nerve defect degree of slight group,moderate group and severe group was respectively (15.83±2.51) μmol/L,(18.99±4.24) μmol/L and (13.13±3.98) μmol/L,P>0.05,and the differences between different groups were not statistically significant.Patients in the experimental group were followed up for 1 years,and the level of plasma Hcy in the no outcome patients with as (16.31±1.54) μmol/L,but the average plasma Hcy of disability or death patients was (20.43±3.01) μmol/L,and the difference was statistical significance(χ²=22.571,P=0.008). Conclusion The plasma homocysteine level in patients with cerebral infarction can significantly increase and be related to the degree of neurological deficit,which is sensitive indexes of cerebral infarction patients in the course of disease monitoring and prognosis.