Objective;To investigate the changes of Tolllike receptor 2 and 4 gene expression in lungs with acute injury induced by acute hemorrhagic necrotizing pancreatitis(AHNP) in rats. Methods;Forty SD male rats were randomly divided into shamoperated group(n=10), and AHNP group(n=30). Of all the rats, the lungs were dissected for lung histological scores and bronchoalveolar lavages were harvested for lung injury index. TLR2,4mRNA expression in the lungs was measured by RTPCR at different time points. Results;TLR2,4mRNA could be detected in lungs with low values in shamoperated group; but they were markedly increased at 3 hours in AHNP group, peaking at 6~12 hours(P<0.05 or P<0.01). Conclusions;These data suggestal that expression of TLR2/4mRNA is increased in lung tissuse in AHNP rats, and upregulation of TLR2,4mRNA expression in lung tissuse may be involved in the development of acutelung injury induced by AHNP.