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Background / Objective: Although postoperative adjuvant chemotherapy for pancreatic carcinoma improves survival in some patients, the efficacy varies by individuals, and the results remain unsatisfying. Gemcitabine plays an important role in adjuvant chemotherapy for not only unresectable but also resected pancreatic carcinoma. However, the problem is that a substantial number of patients have a resistance to gemcitabine. The aim of this study was to clarify which is more useful as a predictive marker of adjuvant gemcitabine-based chemotherapy for pancreatic carcinoma after surgical resection, intratumoral human equilibrative nucleoside transporter 1 (hENT1) or ribonucleotide reductase regulatory subunit M1 (RRM1) expression. Methods: Intratumoral hENT1 and RRM1 expression were examined by immunohistochemistry in 109 pancreatic carcinoma patients who received adjuvant gemcitabine-based chemotherapy after surgical resection from January 2002 to May 2011. Relationships between clinicopathological factors, including hENT1 and RRM1 expression, and disease free or overall survival (DFS or OS) were evaluated by univariate and multivariate analyses. This study was a retrospective analysis on retrospectively collected tissue and data. Results: High intratumoral hENT1 and RRM1 expression was observed in 78 (72%) and 44 (40%) cases, respectively. DFS rates for all 109 patients were 59% at 1 year, 42% at 2 years, and 26% at 5 years, and OS rates were 81% at 1 year, 61% at 2 years, and 31% at 5 years, respectively. In univariate analysis, both hENT1 and RRM1 expression were significantly associated with DFS (hENT1: P = 0.004, RRM1: P = 0.011) and OS (hENT1: P = 0.001, RRM1: P = 0.040). In multivariate analysis, the both were identified as independent factors for DFS (hENT1: P = 0.001, RRM1: P = 0.009) and OS (hENT1: P = 0.001, RRM1: P = 0.019). The evaluation of the combination of the both was also identified as a powerful independent predictor for DFS (P < 0.001) and OS (P < 0.001). Conclusions: Both hENT1 and RRM1 expression is useful as a predictive marker of adjuvant gemcitabine-based chemotherapy for pancreatic carcinoma after surgical resection. In addition, combined analysis of the two is even more useful.