2,4,5-Trifluorobromobenzene is a valuable intermediate with important application in the synthesis of biologically active peptides and fluorescent reagents. A continuous-flow system has been successfully developed for the synthesis of 2,4,5-trifluorobromobenzene in a microreactor using FeBr3 as a catalyst, which is steadily generated in situ from the reaction of Br-2 and Fe. The procedure is efficient and easy-to-handle, and 2,4,5-trifluorobromobenzene can be obtained within minutes in high yields.