Objective To evaluate the cognition of Senile Metabolic Syndrome (MS) patients and to investigate the relationship between metabolism-related indices and MCI. Methods 74 cases with MS (MS group), 45 patients with vascular risk factors (NMS group) and 32 normal controls were enrolled. Mini- mental state examination (MMSE), Montreal cognitive assessment (MoCA), Digit-Symbo1 Test (DST), Auditory verbal memory test (AVMT), Trail making test(TMT), Sunderland clock drawing test(CDT), and verbal Fluency test (VFT) were applied to evaluate cognitive function. Biochemical variables were measured by routine methods. Results ① The incidences of MCI in the MS and NMS groups were 52.7% and 33.3% respectively. There was statistical difference in incidence between the two groups (P<0.01); ② The levels of waist circumference, body-mass index(BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), and triglycerides (TG) in the MCI group were higher than those in the nonMCI group(P<0.05); ③ The general cognition function in the MS and NMS groups was significantly lower than that in the control group(P<0.001). MS cases achieved significantly lower scores than NMS cases in memory, orientation, attention and executive function(P<0.01); ④ The scores of MoCA, DST, AVMT and TMT in MS group were lower than those in the NMS group(P<0.05); ⑤ The four most related risk factors affecting cognitive domain of MCI patients were FBG, blood lipids, SBP and waist circumference. The severity of cognitive impairment was directly associated with the level of metabolic indexes. Conclusions Elderly patients with metabolic syndrome show a deterioration in memory, calculation, attention and visuospatial perception. Patients with MCI often have accompanying metabolic dysregulation, and there is positive correlation between the number of abnormal metabolism-related indices and the degree of cognitive impairment.