Objective To investigate the role of nuclear factor κB (NF-κB) in the induction of MMP-3 protein by TNF-α in colon cancer cells and the effect of antioxidant on the induction of MMP-3.Methods ELISA was used to detect the concentrations of MMP-3,NF-κB in the cell nuclei was detected with electrophoretic mobility shift assay.Results MMP-3 protein expression induced by TNF-α was blocked by pyrrolidine dithiocarbamate (PDTC).TNF-α triggered the activation and translocation of NF-κB and PDTC inhibited the activation of NF-κB induced by TNF-α.Conclusions The induction of MMP-3 protein by TNF-α is dependent on the activation of NF-κB.Antioxidants may inhibit the induction of MMP-3 protein through the inhibition of NF-κB activation.