Abstract: Objective To investigate the correlation between excision repair crosscomplementation1（ERCC1） expression in tumor tissue and peripheral blood lymphocytes（PBLCs） from gastric cancer，and their expression with clinical features. Methods A total of 53 patients with gastric cancer receiving surgery were studied.ERCC1 protein expression in tumor tissue and PBLCs were determined by immunohistochemical staining. Another 20 cases of PBLCs from gastrointestinal benign disease and the health were collected as control. Results The positive expression rates of ERCC1 were 67.9％，56.6％ and 10.0％ in tumor tissues，PBLCs of gastric cancer，and PBLCs of control group. The expression of ERCC1 in PBLCs of gastric cancer was much higher than that in PBLCs of control group（P＜0.05）. There was no relation between the ERCC1 expression and the clinical characteristics including age，gender，histological type，clinical stage，T stage，metastasis of lymph node and degree of differentiation.The PBLCs ERCC1 expression correlates with the expression in tumor tissues（r=0.475， P=0.000）. Conclusion In gastric cancer，the ERCC1 expression in PBLCs can indirectly reflect the ERCC1 expression in cancer tissues.