Background and purpose:TGF-?/EGFR autocrine loop is markedly activated in wide malignant tumor. It is closely correlated with the tumorigenesis and development of different cancers. Our study is to investigate the biological behavior and signaling molecule changes in TGF- induced ovarian cancer cell line Caov-3, and to study the effect and molecular mechanism of the activation of TGF- /EGFR autocrine loop in ovarian cancer.Methods:The tetrazolium-based colorimetry assay was used to evaluate the cell growth treated by TGF-?. The vitro invasion assay was used to examine the invasiveness of Caov-3 treated by TGF-?.Expression of EGFR、 ERK1/2、PI3K、AKT、P70S6K were determined by western blotting.Results:Exogenous TGF-? enhanced significantly the proliferation and invasiveness of Caov-3 cells. The proliferation rate of Caov-3 was in a dose-dependent manner to TGF-? within the concentration of 0.5~25ng/ml.Exogenous TGF-? up-regulated the expression of EGFR、PI3K、AKT、P70S6K but not ERK1/2.Conclusions:The activation of TGF-?/EGFR autocrine loop could promote the growth,invasion and metastasis of ovarian cancer through PI3K/AKT/P70S6K signaling survival pathway.