Abstract: Objective To investigate the expression of osteopontin (OPN) in non-small cell lung cancer (NSCLC) tissues and its relationship with the prognosis of patients. Methods Immunohistochemistry (IHC) was applied to detect OPN expression in 84 cases of NSCLC tissues. The relationship between OPN expression and clinicopathological factors, overall survival(OS), disease-free survival(DFS) of the patients were analyzed by Chi-square test and Kaplan-Meier survival curve. Results The expression of OPN was 83.3% (70/84) in 84 cases of NSCLC tissues. Moreover, for patients with tumor-node-metastasis (TNM) stage, OS and DFS in OPN negative group were significantly higher than those in OPN positive group (χ ²=9.722, P=0.019; χ ²=6.064, P=0.014), however, there was no significance between the expression of OPN and the prognosis of patients with advanced stage NSCLC. Conclusion OPN is commonly expressed in NSCLC tissues and could be a novel prognostic biomarker for early stage NSCLC patients.