The utility model discloses a solar multi-level spraying evaporation sea water desalting plant. The structure is as follows: a condensation end of a heat-pipe type solar collector is inserted in a position close to the bottom of the plant, a floating ball used for controlling a liquid surface is arranged above the condensation end of the heat-pipe type solar collector, and a concentrated seawater discharge port is formed at the bottom of the plant; an air supply outlet is arranged above the floating ball and on the opposite wall of the plant, the air supply outlet is communicated with an air outlet of an air blower, and a first-stage evaporating pan, a second-stage evaporating pan and a third-stage evaporating pan are sequentially arranged above a certain distance away from the air supply outlet, and are arranged in the sequence from low to high; a draught fan is arranged at the top of the plant, an outlet of the draught fan is connected with an inlet of a coil heat exchanger, and the coil heat exchanger is placed in a seawater storage groove; a water inlet of a centrifugal pump is arranged on the bottom of the plant, and a water outlet is arranged on the upper part of the third-stage evaporating pan; and the seawater storage groove is provided with a seawater outlet. The plant provided by the utility model has the advantages of simple structure, flexible scale, high automaticity, energy conservation and environmental protection.