Background: The aim of this phase I/II study was to evaluate the efficacy and safety of the combined use of docetaxel, cisplatin (CDDP) and 5-fluorouracil (5-FU) (DCF) in patients with recurrent/metastatic squamous cell carcinoma of the esophagus (SCCE). This study adopted divided doses of docetaxel and CDDP in order to reduce the toxicities of the treatment. Methods: The dose of docetaxel was escalated using the following protocol in the phase I stage: level 1, 30; level 2, 35 and level 3, 40 mg/m², which was intravenously infused for two hours on days 1 and 8. CDDP was administered at a dose of 12 mg/m² infused for four hours on days 1-5. The 5-FU was administered at a dose of 600 mg/m²continuously infused from day 1 to 5. This regimen was repeated every four weeks. Results: The study subjects were nine patients (phase I) and 48 patients (phase II). The recommended dose was determined as level 3 in phase I. In the phase II stage, the overall response rate was 62.5%, with a complete response rate of 12.5%. The median progression-free survival was six months, and the median overall survival was 13 months. Grade 3/4 toxicities of leukopenia, neutropenia and febrile neutropenia occurred in 64.6, 68.8 and 14.6% of the patients, while grade 3/4 non-hematological toxicities were relatively rare. No treatment-related death was recorded. Conclusions: This modified DCF regimen can be a tolerable definitive chemotherapy for unresectable SCCE because of its high efficacy, although adequate care for severe neutropenia is needed. Clinical trial information: NCT00915850