Objective To observe the tumor-inhibiting effect and its mechanism of Xiaozheng Powder（Powder for dissolving masses） on mice with H22 transplanted hepatocarcinoma cells.Methods Totally 120 Kunming male mice were selected.The successfully made solid tumor mouse models were of 60 and ascites tumor mouse models were of 60

and blank group was of 10.The solid tumor mice and ascites tumor mice were randomized respectively into the model group

Xiaozheng Powder small-dosage

medium-dosage

and large-dosage groups

5-Fu group

and 5-Fu + Xiaozheng Powder medium-dosage group.Twenty-four hours after inoculation of H22 hepatocarcinoma cells

the mice were medicated according to body weight

once a day for 10 days in succession.The mice of the solid tumor group were weighted and killed 24 hours after stop of medication and their tumors were taken out and weighted for calculating the tumor growth inhibition rate

and the immunohistochemical method was applied to detect the expression of vascular endothelial growth factor（VEGF） and Cyclin-D1.The survival days of the mice of ascites tumor group were recorded to calculate their survival rate.Results Xiaozheng Powder functioned significantly to inhibit the tumors of the solid tumor mice of all groups

compared with the model group

except the Xiaozheng Powder small-dosage group

the difference of all other groups was statistically significant（P<0.01）.Xiaozheng Powder could decrease the expression of VEGF and Cyclin-D1 in the tumor

compared with the model group

except the Xiaozheng Powder small-dosage group

the difference of all other groups was statistically significant（P<0.01）. Xiaozheng Powder could prolong the survival of ascites tumor mice

compared with the model group

the difference of Xiaozheng Powder medium-dosage group was statistically significant（P<0.05）

and the difference of 5-Fu group and 5-Fu + Xiaozheng Powder medium-dosage group was statistically significant（P<0.01）.Conclusion Xiaozheng Powder has the function of inhibiting the tumor and prolonging the life of H22 transplanted hepatocarcinoma mice.The mechanism of inhibiting tumor is possibly related with its down-regulation of VEGF and Cyclin-D1 expression.