The invention discloses a system and method for treating sewage containing salt. The system comprises a pretreating unit, a pre-concentrating unit, an evaporating unit, a crystallizing unit, a condensate fine treating unit and a solid ingredient treating and recycling unit. When pretreating is carried out, the sewage which is to be treated and contains salt is introduced, and waste water and sludge are generated after treatment; pure water and concentrated water are generated in the pre-concentrating process; condensate and strong brine are generated in the evaporating process; condensate and crystallized salt are generated in the crystallizing process, the pure water and the condensate are subjected to a condensate fine treating process, and the sludge and crystallized salt are subjected to a solid ingredient treating and recycling process; recycling water is generated in the condensate fine treating process. By means of the system, customized process selection can be carried out according to different demands, swage discharge to an adjacent water body can be completely eliminated, moisture can be recycled to the maximum degree, high-purity softened water can be obtained to the maximum degree, energy consumption is low, and resource recycling of the salt can be achieved.