Abstract: Objective:To investigate the influences of seawater immersion onliver function and pathological changes after open chest wound in experimental dog. Methods:Twenty health dogs were divided randomly into two groups. A right open pneumothorax was induced in both groups. Control group(n=10) was chest trauma only but seawater immersion group(n=10) had seawater prepared of artificialness immersion after chest trauma. Blood samples were taken before the injunry and at 15,30,45 minutes as well as 1,2,3,4 hours after injury and water immersion,respectively for both groups.Serum bilirubin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and alkaline phosphatase (AKP) were assayed. The pathological changes in hepatic tissue were also studied by light microscope and electronic microscope.Results:The serum bilirubin, ALT,AST and LDH were significantly higher and earlier in seawter immersion group than those in control group. Meanwhile the pathological changes in hepatic tissue in seawater immersion group were much more significiant than those in control group.Conclusions:Liver function and its pathological changes appears to be associated with seawater immersion after chest trauma in experimental dog.