Combination process of coagulation-sedimentation and vertical flow constructed wetlands was used for treating mixed township sewage. By analysis of design parameters and respective decontamination mechanisms of coagulation-sedimentation and vertical flow constructed wetlands, the optimal pH was determined, and the effect of the treatment process was analyzed. The results showed that the combination process had exactly high removal rates for pollutants in mixed township sewage, especially for wastewater containing heavy metal ions, and the water quality of final effluent was good.