The purpose of this research is the evaluation of removal efficiency of THMFP in BAC. The changes of four types of THMFP and total THMFP were examined in the influent and effluent of BAC filter from March to December in 2008. It turned out that the amounts of brominated THMFP were obviously higher in winter and autumn compared to the spring and summer, which also resulted in an increase of the total-THMFP levels during winter and autumn. In addition, long-term running of BAC filter shows the good removal function of chloroform formation potential, but not brominated THMFP; with further bromination, this function was declined, as it shows the formation of bromoform in BAC filter during October and December. These results were caused by changing of the proportion of $Br^-$/DOC.