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[Display omitted] • Prepared ZIF-67/CoFe-LDH has excellent catalytic performance. • DFT demonstrated that oxygen vacancies mediated free radical and non-free radical pathways. • The role of reactive oxygen species in ZIF-67/CoFe-LDH/PMS system was studied. • The SMX degradation pathway was analyzed and the biotoxicity of the degradation intermediates was estimated. Herein, a novel rich oxygen vacancy (Ov) cobalt-iron hydrotalcite composite cobalt metal–organic framework material (ZIF-67/CoFe-LDH) was prepared by simple urea water and heat reduction approach and utilized for the peroxymonosulfate (PMS) system to remove sulfamethoxazole (SMX). 95 ± 1.32 % SMX (20 mg/L) was able to degraded in 20 min with TOC removal of 53 ± 1.56 % in ZIF-67/CoFe-LDH/PMS system. The system maintained a fantastic catalytic capability with wide pH range (3–9) and common interfering substances (Cl−, NO 3 −, CO 3 2−, PO 4 2− and humic acid (HA)), and the degradation efficiency could even remain 80.2 ± 1.48 % at the fifth cycle. Meanwhile, the applicability and feasibility of the catalysts for practical water treatment was verified by the degradation effects of SMX in different water environments and several other typical pollutants. Co and Fe bimetallic active centers synergistically activate PMS, and density functional theory (DFT) predicted adsorption energy about Ov in ZIF-67/CoFe-LDH for PMS was 1.335 eV, and O O bond length of PMS was stretched to 1.826 Å. As a result, PMS was more easily activated and broken, which accelerated the singlet oxygen (1O 2), sulfate radical (SO 4 •−), high-valent metals and other reactive oxygen species (ROS). Radical and non-radical jointly degrading the pollutants improved the catalytic effect. Finally, SMX degradation intermediates were analyzed to explain the degradation pathway and their biotoxicity was also evaluated. This paper provides a new research perspective of oxygen vacancy activating PMS to degrade pollutants. [ABSTRACT FROM AUTHOR]