<h3>Objective:</h3> To eavluate the stroke severity and outcomes in daibetic patients with acute ischemic stroke who had been treating with metformin compared to other diabetic controlling agents in patients with Diabetes Mellitus Type 2 before stroke. <h3>Background:</h3> The effect of metformin in Diabetes type-2 (DM-2) on neural tissue survival encountering ischemia is proposed in experimental studies. It is theorized that this effect is depenant from its effect in controlling blood glucose level. However, in humans the benefit of pre- metformin use on the severity and prognosis of stroke in a clinical setting is yet to be understood. <h3>Design/Methods:</h3> According to the inclusion and exclusion criteria, we extracted data from patients with DM-2 with acute ischemic stroke referred to a Central Stroke Center. Their medications during the diabetes disease (druge history) before stroke were recorded. Symptoms’ severity was measured according to the national institutes of health stroke scale (NIHSS) score on admission. Confounding bias including factors affecting stroke severity and outcome were controlled. Stroke outcome was measured by a modified Ranking scale (mRS), 3 months after stroke onset. The optimal functional outcome was considered a Modified Rankin Scale(mRS) score of 2 or lower. <h3>Results:</h3> Of 126 patients with DM-2, 82 (65.08%) patients had been taking metformin before the stroke and 44 (34.92%) had been receiving other antidiabetic agents. The severity of symptoms measured by NIHSS was similar in both groups. After including confounders in the regression model, there was no meaningful difference between the two groups in functional outcome (p-value>0.053) <h3>Conclusions:</h3> Prior Diabetes treatment with metformin seems not to have a significant effect on either severity of onset or outcomes of acute ischemic stroke in diabetic type 2 patients compared to other diabetic treatments. <b>Disclosure:</b> Dr. Esmaeili has nothing to disclose. Dr. Mirzaasgari has nothing to disclose. Dr. Zabeti has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Alexion. Dr. Zabeti has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Genentech. Dr. Zabeti has received personal compensation in the range of $5,000-$9,999 for serving on a Speakers Bureau for Alexion. Dr. Zabeti has received personal compensation in the range of $50,000-$99,999 for serving on a Speakers Bureau for Biogen. Dr. Zabeti has received personal compensation in the range of $5,000-$9,999 for serving on a Speakers Bureau for Biogen. Dr. Zabeti has received personal compensation in the range of $10,000-$49,999 for serving on a Speakers Bureau for Genentech. Dr. Zabeti has received personal compensation in the range of $10,000-$49,999 for serving on a Speakers Bureau for Sanofi-Genzyme. Dr. Zabeti has received personal compensation in the range of $10,000-$49,999 for serving on a Speakers Bureau for Horizon. Dr. Zabeti has received personal compensation in the range of $10,000-$49,999 for serving on a Speakers Bureau for Janssen . Dr. Zabeti has received personal compensation in the range of $10,000-$49,999 for serving on a Speakers Bureau for BMS.