Objective To study the influences of Yiqi Yangyin Jiedu Fang on the growth and apoptosis of transplanted tumor in mice with Lewis lung cancer（LLC）.Methods The LLC model was established in C57BL/6 mice and then all mice after inoculating LLC were randomly divided into 6 groups

including the control group（A）

group of low-dose Yiqi Yangyin Jiedu Fang（B group）

group of mid-dose Yiqi Yangyin Jiedu Fang（C group）

group of high-dose Yiqi Yangyin Jiedu Fang（D group）

cisplatin（DDP） group（E group） and group of Yiqi Yangyin Jiedu Fang combining DDP（F group

each n=10）.In the next day after inoculation Yiqi Yangyin Jiedu Fang were given to mice intragastrically for 26 days and DDP was injected intraperitoneally every other day.The growth of the transplanted tumor was observed

and the mice were killed on the 28th day for weighing tumor and calculating tumor inhibition rate.The expression of Caspase-3（apoptosis-related protein） was detected by using immunohistochemistry

and apoptosis index

by using TUNEL.Results In B

C and D groups

the tumor was significantly inhibited

the tumor inhibition rate was

respectively

19.30%

32.83% and 34.59%

and tumor weight was lower than that in the control group（P<0.01）.The tumor inhibition rate reached 83.71% in F group with a significant difference compared with other groups（P<0.01）.The expression of Caspase-3 was negative in A group

positive in B

C and D groups

which was correlated to dose（P<0.05）

and the strongest in F group compared with other groups（P<0.01）.The detecting of TUNEL showed that Chinese medicinal improved the apoptosis of transplanted tumor cells and this effect was promoted after Chinese medicinal combining with DDP（P<0.01）.Conclusion Yiqi Yangyin Jiedu Fang has an inhibitory effect on the growth of transplanted tumor in mice with LLC.The mechanism may be related to that Chinese medicinal can improve the expression of Caspase-3 and induce apoptosis

and the effect can be promoted after they combining with DDP.