The invention discloses a desulfurization waste water treatment zero-emission processing system and method. The system comprises a boiler sub system, an electric dust removing device, an evaporating device, a desulfurization device, a heat device, a desulfurization waste water tank, a steam turbine sub system, a recycling device, a heat exchange device and a sludge filter pressing device. The system further comprises a related fitting cleaning device, a dosing device, an electrical system and meter control for ensuring the long-term stable operation of the process system, the system has the advantages of less dosing, repeated utilization, partial waste water investment and operating treatment cost saving and the like, and the current problems encountered by industrial waste water zero-emission are solved.