Abstract: The title content was studied by TGA, DSC, pyrolysis-conductance etc. The results show that the flame retardancy of title resin is improved with the introduction of bromine element and the resin will be selfextinguish when the bromine weight content is more than 7.63%. In the meanwhile, bromine element can increase the char-residue and the HBr created by the pyrolysis of the resin can also act as a radical scavenger. The synergistic action can be found when antimony trioxide was added into the brominated bisphenol-A type resin.