Background: Past exposure to human cytomegalovirus has been suggested to participate in the pathogenetic events associated with atherosclerotic lesion establishment and progression. However, whether ongoing human cytomegalovirus infection is related to plaque instability, and subsequent acute cerebral ischemia, is relatively unknown. The purpose of this study was to evaluate the potential relationships between active human cytomegalovirus infection and ischemic stroke, especially in regard to metabolism and inflammation. Methods: Ninety-nine acute ischemic stroke patients, associated with large artery atherosclerosis, were divided into two groups based on the presence or absence of human cytomegalovirus immunoglobulin M (IgM) (human cytomegalovirus-IgM-positive/human cytomegalovirus-IgM-negative -33:66). Baseline clinical characteristics, inflammatory factors, and biochemical assessments were compared in both groups. Then, all patients and human cytomegalovirus-IgM-positive patients were divided into quartiles according to their high-sensitivity C-reactive protein levels, respectively, and risk factors were compared. Finally, correlations between inflammatory factors (high-sensitivity C-reactive protein and white blood cell count) and other atherosclerosis risk factors in both human cytomegalovirus-IgM-positive and -negative subjects were evaluated. Results: An association between human cytomegalovirus-IgM seropositivity and atherogenic modification of metabolism and inflammatory status were not found in this study. Both age and white blood cell count increased across quartiles of high-sensitivity C-reactive protein in all subjects (P=0.001), while age and low-density lipoprotein cholesterol increased across quartiles of high-sensitivity C-reactive protein in the human cytomegalovirus-IgM-positive group (P=0.02 and 0.007, respectively). Multivariate linear regression analysis showed that high-sensitivity C-reactive protein was associated with age in human cytomegalovirus-IgM-positive group (P=0.002), while no other factor was associated with white blood cell count in these subjects. Conclusion: Our study provided no evidence for the direct implication of active systemic human cytomegalovirus infection, represented by human cytomegalovirus-IgM positivity, in the pathogenesis of acute ischemic strokes, particularly those involving plaque instability and metabolic disorders.