Yarn dyed wastewater has to be treated prior to disposal into the water bodies due to its high content of harmful organic compounds. In this study, the performance of Chemical Oxygen Demand (COD) removal and kinetic rate constant are investigated via hybrid electrocoagulation-Fenton in a continuous system using wastewater discharged from a yarn dyed industry in Surabaya city. The wastewater was treated in a batch mode using electrocoagulation to reduce Total Suspended Solid, followed by Fenton method in a continuous system to reduce COD level. Various Fe(II) feeding modes, molar ratio of Fe(II)/H2O2, initial pH of wastewater, and flow rate are used in this study. The results show that COD removal process obeys a pseudo-first order kinetics. At Fe(II)/H2O2 ratio of 1:10, initial wastewater pH of 3.0, and feed flow rate of 30 mL/min, the COD removal efficiency was observed to be 80%, and the kinetic rate constant is 0.07046 min-1. The chemical cost for the treatment estimated to be IDR 160 per L wastewater, which is cheaper than the previously reported batch system of IDR 256/L.