Abstract: The relationship between lncRNA SIL and alveolar epithelial cells on the proliferation and migration in pulmonary fibrosis was investigated. The small interference RNA were designed to silence the expression of endogenous lncRNA SIL, the proliferation and migration of cells after lncRNA SIL silencing were studied by RT-PCR, MTT, Western blot, Cell damage repair experiments and Transwell. Compared with negetive control group, the proliferation ability of cells was increased significantly after lncRNA SIL silencing, and the expression levels of protein PCNA and Ki67 were increased significantly, too. The migration ability A549 cells after lncRNA SIL silencing was increased significantly compared with negetivecontrol group by cell damage repair experiments and Transwell. These results showed that lncRNA SIL silencing can promote the proliferation and migration of A549 cells and it is speculated that lncRNA SIL might be a potential inhibitor of pulmonary fibrosis.