Background: Stroke patients have significantly higher fibrinogen levels. Previous studies revealed that, hyperfibrinogenemia at the beginning of acute ischemic stroke is associated with increased risk of death within one year after stroke. Little is known about the influence of fibrinogen levels on functional outcome. Aim: Investigate the prognostic influence of the change in the plasma fibrinogen levels after acute ischemic stroke on the functional outcome of the patients. Methods: Fibrinogen levels were determined within 24 hours and at day 5 of stroke onset. Modified Rankin Scale (mRS) at 90 days quantified functional outcomes. Pearson’s product correlation coefficient “r” was used to assess linear correlation between fibrinogen levels and mRS. Results Plasma fibrinogen levels are high in patients with acute ischemic stroke. The mean plasma fibrinogen level at the first 24 hours was 3.66 ± 0.796 g/L, while after 5 days was higher with a mean of 4.72 ± 1.669 g/L, with significant correlation with functional outcome at 90 days p