Several studies have stressed the involvement of inflammation in the pathophysiology of acute brain ischemia, but the role of immunoinflammatory activation in diabetic stroke patients has not yet been fully evaluated. The aim of our study was to evaluate immunoinflammatory activation of acute phase of stroke in relation to time of symptoms onset, diabetic state and diagnostic subtype. We enrolled 60 patients (32 diabetics; 28 non- diabetics) with acute ischemic stroke and 123 subjects without acute ischemic stroke, and measured levels of IL-1beta, TNF-alpha IL-6, IL-10, E-selectin, P-selectin, sICAM-1, sVCAM-1, VWF, 24-72 h and 7-10 days after stroke onset; TPA, PAI-1 plasma levels at 24-72h. Our stroke patients exhibited significantly higher plasma levels of cytokines, selectins, adhesion molecules and PAI-1, and diabetic stroke patients exhibited higher plasma levels of PAI-1 in comparison with non-diabetic ones. Lacunar strokes in comparison with those non-lacunar exhibited significantly lower levels of TNF-alpha and IL1-beta P-selectin and ICAM-1. Moreover, diabetic patients with lacunar strokes exhibited a minor grade of immunoinflammatory activation of the acute phase at 24-72h and 7-10 days after stroke onset. The minor grade of immunoinflammatory activation of patients with lacunar strokes, particularly diabetic ones, could be related to the minor extension of the infarct size, owing to the typical microvascular disease of diabetic subjects which could also explain the reported better outcome of this subtype of ischemic stroke.