〔Abstract〕 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 .