〔Abstract〕 Objective To investigate the effect of solasonine regulation of the STAT3 signaling pathway on the bio- logical behavior of lung adenocarcinoma cells．Methods H1299 cells were treated with 0. 125，0. 25，0. 5 and 0. 75 mmol /L solasonine，respectively．The proliferative activity of H1299 cells was detected by CCK-8．The mi- gration and invasion ability of H1299 cells were detected by scratch，Transwell migration and invasion assay．The apoptosis level of H1299 cells was detected by flow cytometry and Hoechest 33258 /PI double staining．The protein expression levels of STAT3，p-STAT3 ，Bcl-2 ，Bax ，Caspase-3 ，Cl-Caspase-3 ，Snail ，Slug ，N-cadherin and E- cadherin in H1299 cells were detected by Western blot assay．Results Solasonine at different concentrations sig- nificantly reduced the proliferation of H1299 cells (P＜0. 05) ．0. 125 and 0. 25 mmol /L solasonine promoted the apoptosis of H1299 cells (P＜0. 05) and inhibited the migration and invasion of H1299 cells (P＜0. 05) ．Solaso- nine inhibited the expression of STAT3，p-STAT3 and Bcl-2 proteins，enhanced the expression of Bax，Caspase-3 and Cl-Caspase-3 proteins．Solasonine inhibited the activation of STAT3 in cells，reduced Snail and Slug protein expression levels，enhanced E-cadherin，reduced N-cadherin(P＜0. 05) ．Conclusion Solasonine can inhibit the activation of STAT3 ，activate the Bcl-2 /Bax / Caspase3 apoptosis pathway ，inhibit the continuous proliferation of lung adenocarcinoma H1299 cells，and promote the apoptosis of lung adenocarcinoma H1299 cells．Meanwhile，it can inhibit the activation of STAT3，reduce the expression of Snail / Slug protein，affect the EMT transformation of lung adenocarcinoma H1299 cells，and inhibit the migration and invasion of lung adenocarcinoma H1299 cells．