A simple and efficient method was developed for the synthesis of 4-phenyl-2-arylaminothiazoles from α-bromoacetophenone and aryl amine in ionic liquid [bmim]SCN. The reaction conditions were optimized. α-Thiocyanatoacetophenone was formed by substitution reaction of α-bromoacetophenone with thiocyanate in [bmim]SCN. After that, 4-phenyl-2-arylaminothiazoles were synthesized in 81.6%～95.2% yields via addition and cyclization of aryl amine with α-thiocyanatoacetophenone catalyzed by acetic acid. Ionic liquid [bmim]SCN could be reused at least five times without significant decrease in yield.