Background:To compare the efficacy of intravenous (Ⅳ) combination low-dose Tissue-type plasminogen activator (t-PA) and urokinase (UK) versus classical IV t-PA or UK alone for acute ischemic stroke (AIS) within 4.5 hours of symptom onset.Methods:153 AIS patients were administrated with three different IV thrombolytic therapies within 4.5-hour time window.Clinical data included age,gender,type of therapy,NIHSS,time from onset to needle,ASPECTS,mRS at 90 day,and medical histories.The outcomes were ANIHSS-a (the difference of NIHSS between at admission and 24 hours) ;ANIHSS-b (between at admission and 7 days),and mRS at 90 days.Multivariate logistic regression (MLR) was used to determine if treatments or other variables could predict these outcomes.Results:Of 153 patients,60.1% had good outcome,and 39.9Yo had poor outcome.The most important predictors of 90-days mRS were AF history (p<0.001) and NIHSS at admission (p=0.001).Age (p=0.004) and treatment type (p=0.043) were also significantly associated with 90-day mRS.Ⅳ t-PA had the best outcome,if compared to low dose t-PA/UK (OR=1.17) and UK alone (OR=1.42).Low dose t-PA/UK also had better outcome than UK alone (OR=1.12).Conclusions:Ⅳ low dose t-PA with UK within 4.5-hour time window was effective and likely comparable to classical Ⅳ t-PA thrombolysis.