Background: Paclitaxel (PTX) is effective in concurrent chemoradiation (CCR) against esophageal squamous cell carcinoma (ESCC) . Which regimen, among cisplatin (DDP) (TP), carboplatin (CBP) (TC) or 5-Fu (TF) in combination with PTX concurrent with radiotherapy, provides best prognosis with minimum adverse events (AEs) is still unknown. Methods: The study compared two pairs of regimens: TF vs. TP and TF vs. TC concurrent with radiotherapy. Patients with histologically confirmed ESCC (clinical stage II, III or IVa) were randomized into the three groups. Patients in TP group were treated with 2 cycles of CCR followed by 2 cycles of consolidation chemotherapy with TP (DDP 25 mg/m²/d, d1-3, PTX 175 mg/m², d1, q28d). Patients in TF group were treated with 6 cycles of TF (5-Fu 300 mg/m², civ 96h, PTX 50 mg/m², d1, qw) in CCR followed by 2 cycles of TF (5-FU 1800 mg/m², civ 72h, PTX 175 mg/m², d1, q28d) in consolidation chemotherapy. Patients in TC group were treated with 6 cycles of TC (CBP AUC = 2, d1, PTX 50 mg/m², d1, qw) in CCR followed by 2 cycles of TC (CBP AUC = 5, d1, PTX 175 mg/m² d1, q28d) in consolidation chemotherapy. The radiotherapy dose in all groups was 61.2 Gy delivered in 34 fractions. The primary endpoint was overall survival and the secondary endpoints were progression-free survival and adverse events. Results: Between July 2015 and January 2018, 321 ESCC patients in 11 centers were enrolled. TP group had a significant higher incidence of acute grade 3/4 neutropenia (59.7% vs. 16.8%(TF) or 32.4%(TC)), thrombocytopenia (12.7% vs. 3.5%(TF) or 6.2%(TC)), anemia (6.4% vs. 4.4%(TF) or 4.4%(TC)), fatigue (10.0% vs. 0.9%(TF) or 0.9%(TC)) and vomiting (5.5% vs. 0%(TF) or 0.9%(TC)) than other two groups (P< 0.05). TF group had a significant higher incidence of grade 3/4/5 esophagitis (13.1% vs. 1.8%(TP) or 5.3%(TC)) and pneumonitis (4.4% vs. 0%(TP) or 1.8%(TC)) than other two groups (P< 0.05). One patient in TF group died of acute pneumonitis. One patient in TF group and one in TC group died of acute esophagitis. Conclusions: TP and TF regimen showed different severe AEs in CCR in ESCC patients and TC showed mild AEs. Clinical trial information: NCT02459457