The invention relates to a zero-discharge system and technology of desulphurization waste water based on an ion selective electrodialysis technology. According to the system, a softening pretreatment mechanism comprises a reaction groove, a clarifier and a filter device, and a reduction concentration mechanism is an ED ion membrane device. Fresh water precipitated by the ED ion membrane device is reused as make-up water for a desulfurization system, or is reused through the concentration of a reverse osmosis membrane, reverse osmosis membrane concentrated water returns to the process before softening pretreatment, and circulation treatment is conducted. According to the zero-discharge system and technology, through the treatment of a three-linkage-box technology, lime is adopted and the pH of the lime is adjusted to 9-9.5, no alkali needs to be added to adjust the pH to 11 or above, the addition amount of the lime is small, few calcium ions are carried in, the calcium ions can generate precipitated sodium carbonate or sodium sulfate without adding more calcium ions, and after clarification and precipitation, filtered water directly enters the ED ion membrane device to be reduced and concentrated. Compared with the prior art, the technology processes are short, the operation and investment cost is low, the system is convenient to maintain, the ion selective electrodialysis technology is adopted, and the system has the advantages of being long in service life, low in requirement for water quality, high in concentration multiple, low in operation load and little in energy consumption.