For eliminating organic pollutants from wastewater, Fe-0 or Fe-0-composites as catalyst for peroxymonosulfate (PMS) activation have attracted increasing attention in advanced oxidation processes. In this work, a novel Fe-0-montmorillonite composites (Fe-Mt-C-H-2) have been prepared by thermal reduction and used as an activator for PMS to remove bisphenol A (BPA). The removal efficiency of BPA (25 mg.L-1) and total organic carbon (TOC) were 99.3% and 70.6%, respectively, in the presence of Fe-Mt-C-H-2 (0.4 g.L-1) and PMS (1 mM) at pH of 3. Electron paramagnetic resonance (EPR) spectroscopy and radical scavenger studies demonstrated that superoxide radical (O-2(center dot-)) and singlet oxygen (O-1(2)) were the crucial reactive oxygen species (ROS) in the Fe-Mt-C-H-2/PMS system rather than sulfate (SO4 center dot-) and hydroxyl radical (center dot OH). Besides, it was found that pH had a great influence on the catalytic oxidation rate of BPA and the Fe-Mt-C-H-2 exhibited best catalytic performance and reusability at initial pH of 3. Furthermore, the constituents of the iron surface oxidation layer at different initial pH were investigated with X-ray photoelectron spectroscopy studies, which indicated that the major constituents were Fe3O4 in acidic solution and contained alpha-Fe2O3, FeO and FeSO4(s) in alkaline or neutral solution. The findings of this study provide new insights into the activation mechanism of PMS by Fe-0-composites and exhibit a promising application of Fe-Mt-C-H-2 in wastewater treatment.