The mumber of Polymorphonuclear leukocyte (PMN) in hepatic tissue increased in the rats with cholangitis, PMN infiltration was mainly in the hepatic sinus in the early stage; and PMN infiltration presented around the hepatocytes 12 hours after infection. Degeneration and necrosis of the hepatic cells was also observed in the rats with acute cholangitis. Only 40 percent of the rats survived 24 hours after infection. Depletion of circulating PMN decreased the damage and necrosis of hepatocytes and improving the survival rate of the infected rats. The results suggest that PMN infiltration plays an important role in hepatic damage in acute cholangitis.