BACKGROUND: The prognosis of syncope is related to the severity of the underlying disease, including cerebral disease, rather than of the syncope itself. The aim of this study was to identify the clinical factors related to the cerebral comorbidity confirmed on brain imaging of syncope patients. METHODS: We retrospectively reviewed the medical records of patients who were diagnosed as syncope and underwent brain magnetic resonance [MR] imaging between January 2011 and December 2014. An abnormal MR lesion was defined as the presence of one or more of the following: (1) ischemic lesion, (2) major cerebral artery occlusion or stenosis over 50%, (3) cerebral aneurysm or vascular abnormalities, and (4) other traumatic or parenchymal lesion. The findings of electroencephalography and clinical factors that might be related to abnormal lesions in brain MR images were investigated. RESULTS: Of 347 (mean age 50.5 years, 48.1% females) patients, abnormal imaging findings were observed in 48 (13.8%). The clinical factors related to abnormal findings were age, hypertension, diabetes mellitus, and coronary artery disease. Independent factors for an abnormal MR lesion were age (odds ratio=1.05, 95% confidence interval [CI] 1.03-1.08, p <0.001) and hypertension (odds ratio=2.73, 95% CI 1.34-5.60, p=0.006). Abnormal electroencephalography findings were noted in 52 (20.3%) of 256 investigated patients. Generalized or focal slowing was observed more frequently in elderly patients (p<0.001) and in the presence of abnormal brain MR lesions (p=0.013). CONCLUSIONS: In syncope patients with hypertension or who are elderly, a brain MR image may be helpful for detecting comorbid brain lesions.