Our study shows that DHEA can down regulate the expression of FASTKD2, it can promote the fusion of mitochondria, inhibit the mitochondrion division, disturb the balance of mitochondrial dynamics, and make the compensation of other pathways unable to continue, resulting in the accumulation of reactive oxygen species in tumor cells, and inhibit the proliferation and growth of lung adenocarcinoma cells. This evidence concerns the gene FASTKD2 and lung adenocarcinoma.