Nanoscale zero-valent iron supported on activated carbon (nZVI/AC) was synthesized in liquid phase reduction method. The nZVI/AC was characterized through X-ray diffraction (XRD), scanning electron microscope(SEM) and transmission electron microscope (TEM). The removal of BrO-3 with nZVI/AC under different conditions and the removal mechanisms were assessed. The results showed that nZVI/AC displayed high reactivity to BrO-3, which should be attributed to the synergetic adsorption and reduction ability of AC and nZVI. The removal efficiency of bromate increased as initial pH decreased. NO-3 and SO2-4 had little effect on BrO-3 removal, but could decrease the removal rate. The BrO-3 removal mechanism indicated that bromate in aqueous solution was adsorbed onto nZVI/MAC, which led to the increase of local bromate concentration in the vicinity of iron nanoparticles, and subsequently reduced to innocuous bromide rapidly with nZVI.