In order to clarify the relationship between FST and lung adenocarcinoma, we examined FST levels in serum of patients with lung adenocarcinoma by enzyme-linked immunosorbent assay (ELISA), and analyzed the expression of FST in lung adenocarcinoma tissues by immunohistochemical staining, as well as further investigated the roles of FST in proliferation and apoptosis of lung adenocarcinoma cells. This evidence concerns the gene FST and lung adenocarcinoma.