Abstract: The treatment of desulphurization wastewater is one of the challenges hindering further water saving in coal-fired power plants. In this paper, the typical treatment technologies, including triple box treatment, membrane-based treatment, thermal-based treatment and electrolytic treatment are introduced while the characteristics of limestone/gypsum wet desulphurization wastewater are discussed. The future treatment technologies of desulfurization wastewater should integrate pretreatment, concentration and resource utilization process etc. In particular, pretreatment plays an indispensible role in the removal of dissolved calcium and magnesium ions, colloidal particles and inorganic scale components. Specifically, problems such as decrease of permeation flux, decline of heat transfer efficiency and electrolytic efficiency due to polarization of membrane, fouling of membrane, scaling of heat transfer equipment or resistance increase of electrolytic bath can be avoided in the process of concentration and resource utilization by pretreatment. In order to create conditions for follow-up zero discharge treatment, it is suggested that the pretreatment level of triple box treatment should be strengthened from the view of turbidity reduction and water softening.