Objective To investigate the relationship between systolic blood pressure (SBP) and etiological subtype in patients with cerebral infarction. Methods Retrospective analysis was made on the data of patients with cerebral infarction admitted to West China Hospital of Sichuan University between January 2015 and March 2018. Patients within 24 h of symptom were included. Etiological subtypes were classified according to Trial of Org 10172 in Acute Stroke Treatment criteria. Multinomial logistic regression was used to analyze the correlation between SBP at admission and etiological subtype. Results A total of 944 eligible cases were included, accounting for 37.3% (944/2528) of the total number of registered cases. The mean age was (65.35±14.17) years, and 57.5% (543/944) were male. The median time from onset to admission was 15 h, with 54.7% (516/944) of patients having elevated blood pressure. Among the patients, large artery atherosclerosis, small artery occlusion, cardiogenic embolism, other definite causes and undetermined causes accounted for 24.9% (235 cases), 21.2% (200 cases), 20.0% (189 cases), 1.8% (17 cases), and 32.1% (303 cases), respectively. Multinomial analysis showed that there was a significant negative correlation between SBP at admission and cardioembolic etiology [odds ratio (OR)=0.987, 95% confidence interval (CI) (0.977, 0.998)]; normal SBP at admission [<140 mm Hg (1 mm Hg=0.133 kPa)] was significantly positively correlated with cardioembolic etiology [OR=2.016, 95%CI (1.211, 3.357)]. Conclusion Normal SBP at admission with acute cerebral infarction predicts cardioembolic etiology, which will be helpful for clinicians to make individual decision based on the pathogenesis in the early stage.