Objective：To investigate the expression and distribution of CyPA in nonsmall cell lung cancer (NSCLC) and to evaluate its clinical significance in the development and progression of NSCLC. Methods: The expression of CyPA was examined in 45 NSCLC tissues, 22 paired tumoradjacent tissues and 33 normal pulmonary tissues using tissue microarray immunohistochemistry method. The relationship between CyPA expression in NSCLC and clinic pathological characteristics of NSCLC was analyzed. Results: Expression of CyPA in NSCLC tissues and paired tumoradjacent tissues was significantly higher than that in the normal pulmonary tissues (P<0.05). No significant correlation was found between the expression of CyPA and differentiation and histological types of NSCLC. Conclusion: CyPA is overexpressed in NSCLC tissues, suggesting that CyPA might serve as a biomarker for the development and progression of NSCLC, whose specific role remains to be further studied.