Objective To explore the effect and safety of urinary kallidinogenase combined with edaravone in treating moderate and severe acute cerebral infarction.Methods 84 patients who had acute cerebral infarction were randomly divided into 2 groups,control group was given edaravone,treatment group was added urinary kallidinogenase based on control group,other conventional medical treatments were same.Results After 14 days treatment,the change of National Institute of Health stroke scale(NIHSS)and Activities of Daily Living(ADL)before and after the 14 days were compared.After the treatment,NIHSS of urinary kallidinogenase group and control group both improved (P ＜ 0.01),urinary kallidinogenase group improved more significantly,and had significant difference compared with control group(P ＜ 0.01).ADL level of the two groups both went up(P ＜ 0.01),urinary kallidinogenase group went up more significantly,and had the significant difference compared with controlled group(P ＜ 0.01).Conclusion Uri nary kallidinogenase could selectively expand ischemic vessel,open collateral circulation,and promote the formation of new vessels,if combined with edaravone treating moderate and severe acute cerebral infarction,it could significantly improve the neurological deficit,reduce disability rate and increase the safety.