In this work, a composite material of mesoporous carbon loaded nano zero valent iron (nZVI/MC) wasprepared and used as an activator of persulfate (PS) to degrade sulfamethazine (SMZ). Scanning electronmicroscopy (SEM) images showed nano zero valent iron (nZVI) was dispersed on the surface or in themesopores of mesoporous carbon (MC) without aggregation. nZVI/MC has less surface area(175.63 m2 g 1) than MC (240.83 m2 g 1). The adsorption efficiency of SMZ increased as the MC andnZVI/MC dosages increased. However, its adsorption efficiency decreased as its initial concentration andpH value increased for both the MC and nZVI/MC. nZVI/MC+PS process showed the most effectiveremoval for SMZ, its removal rate reached 69.5%. Catalytic degradation results indicated that materialdosage and temperature enhanced SMZ degradation in the nZVI/MC+PS process, while SMZ initialconcentration had the opposite effect. For the effect of PS concentration, the SMZ removal efficiencyincreased in the beginning and then decreased. Quenching experiments indicated that SO4- wasrelatively more dominant that OH in the process of SMZ degradation, which could also be confirmed byEPR analysis. The main degradation pathways of SMZ were the Smiles-type rearrangement and thenitration of aniline moiety.