Abstract: AIM To investigate the effects of curcumin on the inflammatory cytokine expressions of M0, M1 and M2 macrophages. METHODS THP-1 cells were differentiated to M0, M1 and M2 macrophages and then were treated separately by different doses of curcumin (0 μmol/L, 7.5 μmol/L, 15 μmol/L, 30 μmol/L). Using real-time reverse transcription polymerase chain reaction (real-time PCR) and ELISA assay, the expressions of TNFα, IL-6 and IL-12 in each group were detected. RESULTS Compared with those in the control group, cytokine protein and mRNA expressions of TNFα, IL-6 and IL-12 were suppressed by curcumin in M0, M1 and M2 macrophages (P<0.01). Protein expression and mRNA expression both reduced with the increasing of the concentration of the curcumin, respectively. CONCLUSION Curcumin could remarkably suppress the synthesis of cytokine expressions of M0, M1 and M2 macrophages in a dose-dependent manner. Further studies are needed to verify the molecular mechanism of curcumin on macrophage polarization.