Abstract: The technical conditions of treating treated water of dyeing wastewater by electrolysis method with Aluminum electrode were studied, and the optimal technical conditions of electrolysis :I=400mA,t=16.5min, pH=6 were obtained based on lots of experiments. After the treatment, the rates of CODcr and Fe removal were 37.8% and 97.8% respectively. A useful treating process was brought out and its effluent was completely meeting with the standard for process water of dyeing and printworks. Environmental and economic benefits were obtained by applying the process.