PURPOSE: It has been reported that the overexpression of the excision repair cross-complementing 1 (ERCC1) gene, which is essential for the repair of cisplatin (CDDP)- DNA adducts, negatively influences the effectiveness of CDDP-based therapy for primary gastric cancer. We investigated whether the ERCC1 expression was associated with survival for gastric cancer patients in an adjuvant setting. MATERIALS AND METHODS: We retrospectively analyzed 44 patients who were diagnosed with stage II or higher disease after undergoing curative resection and they had also received cisplatin-based chemotherapy. The ERCC1 expression was examined by performing immunohistochemical (IHC) staining, and this was divided into two groups according to the percentage of IHC staining of the tumor cell nuclei (negative: 10% or less, positive: more than 10%). RESULTS: Among the 44 patients (ERCC1-negative/ERCC1-positive group=16/28), 32 patients were male and their median age was 52 years. There was no difference for the baseline characteristics of the two groups. The median follow-up duration was 41 months. The median disease-free survival (DFS) and the overall survival (OS) for the ERCC1-positive group were significant higher than those of the ERCC1-negative group (DFS: 40.4 vs. 14.6 months, p=0.02, OS: undefined vs. 20.4 months, p=0.008). CONCLUSION: The overall survival in gastric cancer patients who received cisplatin-based adjuvant chemotherapy after a curative resection is higher in those patients showing the overexpression of the ERCC1 gene. However, prospective studies using the ERCC1 gene expression as a prognostic marker for the DNA repair activity are needed.