Objective To investigate the relationship between bone morphogenetic protein-7（ BMP- 7） level and the severity and prognosis of patients with acute cerebral infarction（ ACI）. Methods A total of 105 patients with ACI（ ACI group） and 105 healthy people（ control group） were recruited from September 2017 to March 2018. The serum BMP-7 level was measured and the clinical data of all patients were recorded. The patients in ACI group were followed up for 3 months and their Modified Rankin Scores（ mRS） were recorded. The difference of BMP-7 level in ACI group and healthy control group， and the relationship between BMP- 7 level and severity and prognosis in ACI group were observed. Results The level of BMP-7 in ACI group was lower than that in the control group. The result of Logistic regression showed that smoking， hypertension， diabetes， coronary heart disease， cystatin C， glycosylated hemoglobin， and BMP-7 levels are closely related to the incidence of ACI（ P ＜ 0.05）. The level of BMP-7 in less severe ACI group was 61.54（58.46，66.32）， which was higher than that in severe group 54.69（51.18，58.27）. The level of BMP-7 was negatively correlated with the score of the National Institutes of Health Stroke Scale（ NIHSS）（ r=-0.702，P ＜ 0.05）. The level of BMP-7 in patients with poor prognosis was lower than that in patients with good prognosis（ P ＜ 0.05）. There was a negative correlation between the level of BMP-7 and mRS score of ACI patients（ r=-0.493，P＜ 0.05）. Conclusions BMP-7 is an influential factor in the pathogenesis of ACI， and the level of BMP-7 can be used to evaluate the severity of ACI and predict the prognosis of patients with ACI.