BACKGROUND Oxaliplatin has shown promising activity in metastatic gastric cancer (MGC) and has synergism with 5 fluorouracil. This phase II study was performed to evaluate the efficacy and safety of FOLFOX4 regimen in MGC. METHODS Patients with MGC, aged 18-70 years, performance status ≤2, no prior chemotherapy, received FOLFOX4 regimen every 2 weeks as oxaliplatin 85 mg/m 2 IV infusion on day 1 and leucovorin 200 mg/m 2 IV infusion followed by fluorouracil 400 mg/m 2 IV bolus and 600 mg/m 2 22-hour continuous infusion on days 1 and 2. Treatment was administered until progression, unacceptable toxicity, patient's refusal or for a maximum of 12 cycles. RESULTS From August 2007 to June 2010, 34 patients were prospectively enrolled. The median age was 52 years (28-69). In total, 293 cycles were administered with a median of 8 cycles per patient (range 1-12 cycles) and 33 of 34 patients were assessable for treatment response. The overall response rate were 53% with one patient(3%) had complete response, 17 patients (50%) had partial responses and 6 patients (18%) had stable disease. The median survival of all patients was 12.1 months and the median time to progression was 9.4 months. The most common grade 3/4 toxic effects were neutropenia in four patients (12%), diarrhea in three patients (9%), vomiting in two patients (6%) and peripheral neuropathy occurred in three patients (9%). CONCLUSIONS The FOLFOX4 combination chemotherapy showed a very promising antitumor activity and was generally well-tolerated as a first-line treatment of patients with MGC.