Background: For patients who underwent curative-intent upfront surgery, adjuvant chemotherapy is the current standard of care. The previous, randomized phase 3 ESPAC-4 study showed significantly improved overall survival (OS) with GEMCAP compared to GEM. However, this study was conducted in European countries and its implication in Asian patients has not been explored yet. We conducted a retrospective analysis to evaluate the efficacy and safety of GEMCAP compared to GEM regimen. Methods: Between January 2017 and December 2020, a total of 292 patients who received adjuvant GEM or GEMCAP after curative-intent surgery in Asan Medical Center, Seoul, Korea, were included in this retrospective analysis. Results: Adjuvant GEM and GEMCAP were administered in 161 patients (55.1%) and 131 patients (44.8 %), respectively. Compared the GEMCAP group, age of patients were significantly older in the GEM group (median 66 vs 63 yo, p = 0.025); otherwise, there was no significant difference in baseline characteristics between two groups. With the median follow-up duration of 39.4 months (95% CI 36.9 - 45.0 months) in GEM group and 39.4 months (95% CI 34.7-41.6 months) in GEMCAP group, the median OS was 36.8 months (95% CI 29.7-43.5 months) and 46.1 months (95% CI 31.5 months – not reached) in the GEM group and GEMCAP group, respectively (unadjusted HR 0.72, 95% CI 0.51-1.02, p = 0.065). The median recurrence-free survival was 14.3 months (95% CI, 12.9-17.7 months) and 17.0 months (95% CI, 13.3-28.8 months) in the GEM group and GEMCAP group, respectively (p = 0.52). In the GEMCAP group, hand-foot skin reaction (any grade, 15.27 % vs 0.62 %, p < 0.001), neutropenia (78.6% vs 67.7%, p=0.037) and thrombocytopenia (30.53% vs 20.5%, p=0.035) were more common in the GEMCAP group compared to the GEM group. In multivariate analysis, adjuvant GEMCAP was significantly associated with better OS compared to adjuvant GEM (adjusted HR 0.64, 95% CI, 0.44-0.91, p = 0.014). Otherwise, moderate or poor histologic grade, lymph node positive, positive resection margin, and elevated CA 19-9 levels (> median) were significantly associated with poorer OS. Conclusions: In this retrospective analysis for Korean patients, adjuvant GEMCAP showed consistent clinical outcomes shown in the ESPAC-4 trial. As mFOLFIRINOX is the new standard of care for medically fit patients with resected pancreatic adenocarcinoma, further evaluation of optimal adjuvant chemotherapy in daily practice is warranted.