Background In Egypt, circulatory system diseases are responsible for one-third of the annual deaths. Stroke comes 3rd after heart diseases and liver diseases. Stroke includes two types: ischemic and hemorrhagic. The sirtuins (SIRTs) are a family of histone deacetylases that are nicotinamide adenine dinucleotide (NAD)+ dependent. They are activated under conditions of decreased cellular energy stores and are involved in the control of several physiological processes. Objectives To measure the plasma levels of SIRT1 in acute cerebrovascular stroke, to assess its role as a possible biomarker in predicting the risk of acute cerebrovascular stroke, to compare its levels between the two groups of stroke patients, and to evaluate the association between its levels and the severity of stroke. Also, to assess the correlations between the plasma SIRT1 levels and the variables that might play a role in the severity of acute cerebrovascular stroke. Methods This is a case-control study carried out on one hundred and eight participants. The participants were divided into two groups: group A (control group) included fifty-four individuals. Group B (acute cerebrovascular stroke group) included fifty-four stroke patients of two subgroups: B1: twenty-eight patients suffering from acute ischemic stroke and B2: twenty-six patients suffering from acute hemorrhagic stroke. Measurement of the plasma levels of SIRT1 was performed using the enzyme-linked immunosorbent assay (ELISA). Results Regarding SIRT1 levels, acute stroke groups were significantly lower than the control group with no significant difference between ischemic and hemorrhagic groups. There were positive correlations between SIRT1 levels and each of the hemoglobin levels and serum potassium levels. There were negative correlations between SIRT1 levels and each of triglycerides (TG) and stroke score. Conclusion Plasma levels of SIRT1 are lower in patients with acute cerebrovascular stroke than in control. Furthermore, SIRT1 may act as a possible biomarker for predicting the risk of acute cerebrovascular stroke.