The invention relates to a combined treatment method for sodium chloride-containing wastewater generated in dressing and smelting of rare earth. According to the method, a series of desalination and concentration treatments such as deoiling, neutralizing, homogenizing, aeration, flocculation, ultrafiltration, nanofiltration, reverse osmosis, electroosmosis and MVR (mitral valve replacement) concentration are carried out on the wastewater, so that recyclable purified water is obtained; ammonium bicarbonate is added into the sodium chloride extracted from the wastewater, so that the sodium salt can be converted and regenerated into sodium bicarbonate, sodium carbonate and ammonium chloride products for dressing and smelting of the rare earth. According to the method, the recovery rate of the wastewater is high, the effluent quality is stable, the conversion rate of the sodium salt is high, and no three wastes are discharged; production equipment is compact, simple to operate, and easy to realize automation control; the problem that the sodium chloride-containing wastewater and other similar industrial wastewater generated in dressing and smelting of rare earth are difficult to recycle is solved.