Background:: Symptomatic intracranial hemorrhage (sICH) is the most unwanted adverse event in patients with acute ischemic stroke who received intravenous recombinant tissue plasminogen activator (i.v. rt-PA). Many tool scores are available to predict the probability of sICH. Among those scores, the Sugar, Early infarct sign, hyperDense middle cerebral artery, Age, Neurologic deficit (SEDAN) gives the highest area under the curve-receiver operating characteristic value. Objective:: We aimed to examine any factors other than the SEDAN score to predict the probability of sICH. Methods:: Patients with acute ischemic stroke treated with i.v. rt-PA within 4.5 h time window from January 2010 to July 2012 were evaluated. Compiling demographic data, risk factors, and comorbidity (hypertension, diabetes mellitus, dyslipidemia, atrial fibrillation (AF), ischemic heart disease, valvular heart disease, previous stroke, gout, smoking cigarette, drinking alcoholic beverage, family history of stroke, and family history of ischemic heart disease), computed tomography scan of patients prior to treatment with rt-PA, and assessing the National Institutes of Health Stroke Scale (NIHSS) score for the purpose of calculating SEDAN score were analyzed. Results:: Of 314 patients treated with i.v. rt-PA, there were 46 ICH cases (14.6%) with 14 sICH (4.4%) and 32 asymptomatic intracranial hemorrhage cases (10.2%). The rate of sICH occurrence was increased in accordance with the increase in the SEDAN score and AF. Age over 75 years, early infarction, hyperdense cerebral artery, baseline blood sugar more than 12 mmol/l, NIHSS as 10 or more, and AF were the risk factors to develop sICH after treated with rt-PA at 1.535, 2.501, 1.093, 1.276, 1.253, and 2.492 times, respectively. Conclusions:: Rather than the SEDAN score, AF should be a predictor of sICH in patients with acute ischemic stroke after i.v. rt-PA treatment in Thai population.