Abstract: Objective To explore the effects of excision repair cross-complementing 1（ERCC1） and ribonucleotide reductase subunit （RRM1） protein expression on survival prognosis of stage I-IIIa non-small cell lung cancer（NSCLC） patients. Methods ERCC1 and RRM1 protein expression was detected in stage I-IIIa NSCLC patients using immunohistochemistry.The survival prognosis of the pa-tients was analyzed by survival analysis. Results Neither ERCC1 nor RRM1 expression was associated with gender，age，histological type，or TNM stage.The survival prognosis of ERCC1-and RRM1-positive patients in stage Ia was better than that of ERCC1-and RRM1-positive patients in other stages.ERCC1-negative patients in stage Ib-IIIa may benefit from platinum-containing chemotherapy，which may provide a survival advantage.RRM1-negative patients were sensitive to gemcitabine， which provided a survival advantage. ERCC1 expression positively correlated with RRM1 expression（P<0.05） in stage I-IIIa NSCLC patients. Conclusion Chemotherapeutic effect and prognosis of patients with stage I-IIIa NSCLC can be predicted by detecting ERCC1 and RRM1 expression，which may allow for individualized treatment plans.

Key words: Lung neeplasms, ERCC1, RRM1, Individualized chemotherapy, Prognosis