Abstract: AIM：To investigate production of TNFα from murine peritoneal macrophages stimulated with LPS, A₂₃₁₈₇, PMA, fMLP and fMLPP. METHODS: L929 cytotoxicity was used to show the level of released and cell-associated TNFα from murine peritoneal macrophages measured by means of crystal violet staining assay. RESULTS: LPS(0.1～10 μg.mL^-1) and A23187(0.01～1　μmol.L^-1) were shown to induce a dose-dependent increase of both released and cell-associated TNFα, whereas, PMA(0.01～1 μmol.L^-1), fMLP(0.025～2.5 μmol.L^-1) and fMLP(0.025～2.5 μmol.L^-1) did not induce macrophages to produce TNFα. CONCLUSION: LPS and A₂₃₁₈₇ can induce production of TNFα from macrophages. Further research should be performed to study the pathways such as CD14 and calcium ion that may be involved in the biosynthesis of TNFα.