Objectives To evaluate the effects of external application of Xiaozhang Tie on ascites and the mechanism related to vascular permeability of peritoneum and liver in cirrhotic mice.Methods Dimethylnitrosamine was injected intraperitoneally for four weeks to induce liver cirrhosis in mice.After ascites were identified by ultrasound, the animals were randomly divided into five groups (n=10 each) : model (untreated control) ;placebo (plaster matrix only control) , low-dose Xiaozhang Tie (0.125 cm2 plaster) ;mid-dose Xiaozhang Tie (0.25 cm2 plaster) ;and high-dose Xiaozhang Tie (0.5 cm2 plaster) .Uninduced mice (n=10) were used as normal controls.Xiaozhang Tie (652.9 mg crude drug/kg weight) was applied by external application to the umbilical once daily for one week.The amount of ascites, abdominal circumference, and body weight were recorded.Inflammation and fibrosis of liver tissue were observed by hemotoxylin-eosin and Sirius rose staining.Serum alanine aminotransferase (ALT) , albumin, total bilirubin (TBil) , and nitric oxide (NO) were tested.Liver expression of vascular endothelial growth factor (VEGF) was assessed by Western blotting.Evans blue (EB) staining in ascites and liver tissue was used to evaluate vascular permeability of peritoneum and liver.Results Before external application, the abdominal circumference and body weight of cirrhotic mice were comparable.After external application, amount of ascites, abdominal circumference, body weight, ascites index, EB in ascites and liver tissue, serum NO, and VEGF protein expression in liver tissue were all higher than in the normal group.The amount of ascites in the placebo group and model group was similar.Compared to the placebo group, the amount of ascites and ascites index were lower in the Xiaozhang Tie mid-dose and high-dose groups.The abdominal circumference and body weight were lower in the high-dose group than in either the placebo or low-dose groups.Three dosages of Xiaozhang Tie did not produce any observable effects on liver function or pathology.Compared to the model group, EB in ascites, serum NO, and VEGF protein expression in liver tissue were obviously decreased in the Xiaozhang Tie mid-dose group.Conclusion Xiaozhang Tie administered as 0.25 cm2 plaster external application may reduce ascites in cirrhotic mice.Furthermore, the mechanism of this effect may involve attenuation of VEGF expression in liver tissue, reduction of the NO level in serum, and resolving the abnormally higher vascular permeability in peritoneum.