Abstract: Objective To investigate nuclear factor kappa B (NF-κB) activation induced by lipopolysaccharide (LPS) in rat peritoneal macrophages (PMAs) and the inhibitory effect of resveratrol on NF-κB activation. Methods PMAS from normal SD rats were randomly divided into 7 groups, including a control group, a LPS group and 5 resveratrol groups (I-V). PMAs of the control group were incubated in DMEM, and those in LPS group in DMEM containing LPS (10 μg/ml). PMAS of resveratrol groups I-V were incubated in DMEM containing LPS (10 μg/ml) and different concentrations of resveratrol. After 24 h of incubation, NF-κB activation in the PMAs was determined, and the expression levels of tumor necrosis factor alpha (TNF-α), interleukin-1 (IL-1) and nitric oxide (NO) in the culture medium were measured. Results Exposure to LPS resulted in an excessive enhancement of cytokine and NO expressions in the PMAs. Resveratrol at 1.25-10 μg/ml produced a dose- dependent inhibition of cytokine and NO expressions and on NF-κB activation in LPS-stimulated PMAs. Conclusion Resveratrol can inhibit LPS-induced NF-κB activation in rat PMAs and subsequently suppress the expressions of TNF-α, IL-1 and NO.