Printing and dyeing wastewater is one of the universal refractory wastewater, while the amount of azo dye wastewater holds the very major part. The general characteristics of azo dye wastewater are poor biochemical, difficult to process, high COD and high chroma etc.. The development status and research focus of chemical treatment technologies of azo dye wastewater were summarized, and the treatment technologies of wastewater were comprehensively compared. It was pointed out that the types of catalyst should be further explored, the application scope of modified electrode should be extended, and the process efficiency of azo dye wastewater should be improved.