Aim To evaluate the effect of simvastatin on interleukin 6 (IL 6) production in human monocytes stimulated by C reactive protein (CRP) and lipopolysaccharide (LPS), assess the influence of simvastation on monocytes inflammatory reaction. Methods Monocytes were isolated by ficoll density gradient from blood of healthy volunteers. To measure interleukin 6 production(by ELISA) stimulated by 20 mg/L CRP and 10 μg/L LPS at 2 h, 4 h, 8 h, 16 h, 24 h or 1 mg/L, 5 mg/L, 10 mg/L, 20 mg/L CRP and 1 μg/L, 2.5 μg/L, 5 μg/L, 10 μg/L LPS at 24 h, the peaks to be compared with which inhibited by simvastatin(10 -8 mol/L～10 -6 mol/L). Results Interleukin 6 could be produced after being stimulated with 20 mg/L CRP at 4 h and with 10 μg/L LPS at 2 h. The effects of CRP and LPS were dose dependent and time dependent, reaching peaks at 24 h. The highest levels of monocytes IL 6 were 904±77 ng/L, 1 654±765 ng/L in CRP and LPS groups, respectively. Simvastatin (10 -8 mol/L～10 -6 mol/L) inhibited IL 6 production induced by 20 mg/L CRP in a dose dependent manner. Only 10 -6 mol/L simvastatin could inhibit IL 6 production induced by 10 μg/L LPS. Conclusion C reactive protein and LPS induce the production of IL 6 in human monocytes; simvastatin can inhibit the production of IL 6, it may be used in clinical prevention and treatment of coronary heart disease.