In order to consider the prognostic value of hyperdensity of the middle cerebral artery (MCA), we studied retrospectively the medical records of 80 consecutive patients with the diagnosis of ischemic stroke who underwent a non-enhanced computed tomography no longer than 24 h after the onset of the symptoms. To determine the mortality and disability, a follow-up of 30 days was obtained. Mortality does not differ significantly in acute ischemic stroke patients with and without increased density of MCA. When disability, calculated with the Rankin scale, is considered, the two groups are different since patients with hyperdensity of the middle cerebral artery (MCA) have a significantly worse outcome. The two groups do not differ for age, sex, the presence of atrial fibrillation, hypertension, diabetes, myocardial infarction and/or angina, and these factors do not influence the prognosis being equally present in the dead and in the survivors. In the multivariate discriminant analysis with stepwise variable selection, the dense MCA sign was significantly correlated either to mortality or to disability, along with atrial fibrillation, age and diabetes. We conclude that the dense MCA sign can be a useful prognostic factor in the early phase of ischemic stroke.