Considering the putative role of SOX2 in the prognosis and prediction of outcome in NSCLC, a meta-analysis was conducted to determine the association between SOX2 and common clinical and pathologic features of NSCLC. Publications re-using datasets from the same population, the article with more extracted details was included. Studies that did not meet all inclusion criteria were excluded. NSCLC is the leading cause of cancer death, with an overall fiveyear survival rate of less than 15%. New biological markers of NSCLC carcinogenesis may provide important progress in clinical decision making. Emerging evidences have suggested functional molecules involved in cell-cycle control, DNA repair, proliferation, apoptosis that may modulate response to platinum-based chemotherapy and serve as promising biomarkers for individualized chemotherapy and prognosis of NSCLC patients. SOX2 expression plays a critical role incell cycle control, DNA damage response and long-term self-renewal in neural stem cells. Moreover, several studies and our data have identified that SOX2 expression correlated with tumorigenesis, chemoresistance, and maintaining the stem cell-like phenotype in cancer cells. Recently, it has been reported that SOX2 expression may serve as a promising biomarker in prognosis of NSCLC, however, these results were contradictory. Therefore, the present meta-analysis, is a quantitative approach to statistically integrate and analyze the association between SOX2 expression and NSCLC clinicopathological characteristics and overall survival. Recent results show that SOX2 is more frequently upregulatedin SCC than ADC patients, which was accordant with our meta-analysis that SOX2 expression was positively associated with SCC compared with ADC. Though SOX2 over-expression was reported to associate with lower tumor grade, smaller tumor size and lower probability of invasion and metastasis and AbMole Ellipticine former and current smoking status, here our results showed that SOX2 positive expression was not correlated with these clinicopathological parameters. Simultaneously, reports also indicate that SOX2 amplification and overexpression have significant, non-significant and contradictory association with outcome in NSCLC. For example, SOX2 over-expression was recently reported to beassociated with better outcome in SCC, but with poor outcome in early stage lung ADC. Our results found that despite of histology, high SOX2 expression was a positive prognostic biomarker. This finding was supported by the notion of Velcheti et al. that the association SOX2 expression with better survival is independent from the histological subtype. This systematic review has some limitations. First, the number of included studies, as well as the included NSCLC patients in each study, is relatively small. Secondly, though no significant heterogeneity across studies was detected in our study, we could not fully neglect potential heterogeneity.