Abstract: Objective To investigate the role of nuclear factor-kappa B (NF-κB) in the modulation of diallyl trisulfide (DATS) on interleukin-1β (IL-1β) expression in mice with acute lung injury (ALI) induced by lipopolysaccharide (LPS). Methods Mice were randomly divided into Control group, ALI group, DATS group, DATS prevention group and DATS treatment group. The expression of IL-1β mRNA in the lung tissues was detected by reverse transcription PCR (RT-PCR). NF-κB activity in the lung tissues was detected by electrophoresis mobility shift assay (EMSA). The expression of phospho-IκB and IκB were assayed by Western blot. Results The expression of IL-1β mRNA, NF-κB activity and the phospho-IκB expression in lung tissues increased markedly at ALI group (P<0.01, P<0.05), which were inhibited significantly by pretreatment of DATS with ALI mice (P<0.05). However, no significant change was found in DATS treatment group. Conclusions Pretreatment of DATS with ALI mice downregulates IL-1β mRNA expression by inhibiting the phospohrylation of IκB and the subsequent NF-κB activation in lung tissues of ALI mice induced by lipopolysaccharide, which is one of the signal transduction mechanisms of DATS to prevent the occurrence of ALI.