Abstract: In this paper the migration behavior of Ethyl 4- dimethylaminobenzoate( EDB) which was a kind of photoinitiator commonly used in UV ink was studied in food plastic flexible packaging. Three kinds of packaging samples,the actual printing samples,contacting directly photo- initiator samples and contacting indirectly photoinitiator samples,were made in laboratory.3%( w / v) acetic acid,10%( v / v) ethanol and 95%( v / v) ethanol were respectively used as food stimulants.The results showed that the migration behavior of EDB could occur in all three packaging samples,the migration amount of EDB in 95% ethanol was the maximum,and the initial migration rate was the fastest.This indicated that EDB was easier to migrate into fat mimetic. Temperature was higher,migration quantity was larger,and balance time was shorter.