Abstract: AIM To study the inhibitory effects of indomethacin and meloxicam on NF-κB from lipopolysaccharide (LPS) stimulated peritoneal macrophages of mice. METHODS NF-κB was measured with the method of electrophoretic mobility shift assay (EMSA). RESULTS After induction by LPS at the concentrations of 1 and 3 μg.mL-1, the NF-κB content of the mouse peritoneal macrophages increased markedly. Indomethacin and meloxicam, at the concentrations of 10-7-10-5 mol.L-1, decreased the activation of NF-κB at the concentrations of 1 and 3 μg.mL-1 in activated mouse peritoneal macrophages induced with LPS at the concentrations of 1 and 3 μg.mL-1. CONCLUSION The inhibitory effects of indomethacin and meloxicam on NF-κB activation may be one of their mechanisms of antiinflammatory actions.