Abstract: Objective To investigate the expressions of thioredoxin 1(Trx-1) and COX-2 in 63 cases with non-small cell lung cancer. Methods The expressions of Trx-1 and COX-2 were detected in 63 cases non-small cell lung cancer tissues and 20 cases adjacent normal lung tissues by means of immunohistochemical method. Results The positive rates of Trx1 and COX-2 in non-small cell lung cancer tissues were 63.5% and 59.1% respectively，and higher than those in adjacent normal lung tissues(P<0.05).In 20 cases of non-malignant tissue sections，Trx1 and COX-2 expression was observed in 3 and 2 cases，respectively.Trx1 was related to the degree of differentiation.The positive rate of Trx1 in low degree of differentiation was higher than that in high degree(P<0.05).The expression difference of Trx1 between the patients with and without lymph nodes metastasis was also significant(P<0.05).Tumor lymph node metastasis and TNM stage correlated with the expression of COX-2(P<0.05). Conclusion The expression of Trx-1 and COX-2 were closely related to prognosis of non-small cell lung cancer.