Aneuploid is recognized as a hallmark of cancer and is caused by chromosome mis-segregation during mitosis. Recent studies have identified shugoshin (SGO-1) as an important player in proper chromosome segregation and the involvement in tumorigenesis. But, little is known about how SGO-1 is involved. The aim of this study was to obtain information about the role of SGO-1 in human lung cancer cells. In our study, real-time PCR and western blotting assay were performed to detect the expression of SGO-1 in nonsmall cell lung cancer (NSCLC) cell lines. Then, we successfully constructed a lentivirus vector mediating RNAi targeting of SGO-1 (LV-SGO-1 siRNA) and proved that it can suppress the expression of SGO-1 gene in H1299 cells. We found that SGO-1 was highly expressed in NSCLC cancer cell lines. RNA interference of SGO-1 by the LV-SGO-1 siRNA construct significantly decreased SGO-1 protein expression and inhibited the growth and ability of forming colonies of H1299 cells with more cells arrested in G2/M phase, but lentivirus vector control had no effect on H1299 cells. Moreover, suppression of SGO-1 by LV-SGO-1 siRNA increased the apoptosis of H1299 cells with down-regulated Bcl-2 and up-regulated Bax. SGO-1 may provide a novel therapeutic target for the treatment of lung cancer since it inhibits the growth and increases the apoptosis of lung cancer cells.