Background: Perioperative chemotherapy with single regimen either FOLFIRINOX (FFX) or gemcitabine/nab-paclitaxel (Gem/NabP) is the current standard of care for pancreatic and periampullary cancers (PC) with overall survival (OS) of 2-3 years without pre-selected CA19-9 level. Sequential chemotherapy with FFX plus Gem/NabP has recently been investigated in metastatic PC and shown to improve OS. We investigated the outcome of patients who received sequential perioperative chemotherapy FFX plus Gem/NabP. Methods: Patients treated with curative intent surgery for PC who received perioperative sequential chemotherapy FFX plus Gem/NabP (each regimen was given at least two months) were identified. OS and recurrence-free survival (RFS) were calculated from the date of initial treatment (neoadjuvant chemotherapy or resection) to the date of last follow-up/death or recurrence via Kaplan-Meier analysis. Results: A total of 29 patients were identified: 24 (83%) patients had pancreatic cancer, 5 (17%) patients had periampullary cancer; 16 (55%) patients received neoadjuvant chemotherapy FFX plus Gem/NabP; 13 (45%) patients underwent upfront surgery and received adjuvant FFX plus Gem/NabP chemotherapy; 22 (76%) patients had resectable disease, the rest 7 (24%) patients had borderline or unresectable disease were all in the neoadjuvant cohort; node positivity was higher in the adjuvant cohort (n=8, 62%) than in the neoadjuvant cohort (n=8, 50%); 5 (17%) patients were found to have homologous recombination deficiency (HRD: BRCA2, CHEK, BARD, ATM) and received PARP inhibitors as part of the perioperative therapy combination. 10 (34%) patients had CA19-9 ≥ 500. Median age was 65 years (range, 45-79 years), 20 (69%) were male. During the study period, 4 (14%) patients died, and 6 (21%) patients had disease recurrence. Median RFS and OS were not reached with a median follow-up of 28 months (range, 10.9–119 months). The longest RFS was 10 years. The 2-years RFS and OS for the entire cohort was 76.7% and 88.8%, respectively. There was no statistical difference in RFS (log rank HR 1.72, 95% CI 0.23-13.15) or OS (log rank HR 0.99, 95% CI 0.20-4.93) for patients in the neoadjuvant cohort versus adjuvant cohort. Conclusions: Sequential perioperative chemotherapy combined FFX plus Gem/NabP for resected PC is effective and potentially prolongs survival, compared to historical controls who received single regimen.