The utility model relates to an evaporative crystallization system for sewage with high salt content and high organic matter content. The evaporative crystallization system comprises a sodium sulfatefirst-effect evaporation process unit, a sodium sulfate second-effect evaporation process unit, a mixed salt evaporative crystallization process unit, a sodium sulfate drying crystallization process unit, a miscellaneous salt double-effect evaporation process unit and a miscellaneous salt drying process unit which are sequentially communicated, the sodium sulfate one-effect evaporation process unit comprises a raw material tank, the raw material tank is connected with a sodium sulfate one-effect separation chamber through a first sodium sulfate one-effect heating chamber, and a connected outlet of the sodium sulfate one-effect separation chamber is connected with the first sodium sulfate one-effect heating chamber through a second sodium sulfate one-effect heating chamber and a sodium sulfate one-effect axial flow pump; and steam outlets of the first sodium sulfate first-effect heating chamber and the second sodium sulfate first-effect heating chamber are connected with a sodium sulfate live steam condensation tank. The system disclosed by the utility model is stable in operation, good in secondary gas condensate water quality, high in sodium sulfate crystalline salt content, low in impurity salt content and high in sodium sulfate crystalline salt quality, realizes sewage resource utilization, saves the production cost of enterprises and protects the local natural environment.