Dominant bacteria of coke plant wastewater were immobilized by sodium alginate for the treatment of chemical oxygen demand (COD) in coke plant wastewater, and the kinetic model was established. The experimental result indicates that the degradation rates of COD in coke plant wastewater obey Monod equation in the concentration range of 300-1,530 mg L-1. The model parameters were determined by experiment and the value of r(S,max)' and K-S are 239.4 and 1,175.8, respectively. These data would supply useful information for designing immobilized bioreactor.