The invention discloses a method for preparing high-quality salt by using salt manufacturing mother liquor. The method comprises the following technical steps of: mixing feed liquor; heating the feed liquor; concentrating the feed liquor; crystallizing the feed liquor; and post-treating a product. The salt manufacturing mother liquor is fully stirred and mixed with reflux feed liquor in a feed liquor mixing tank under a normal temperature condition; then the mixed feed liquor is heated; the temperature is controlled at 50-70 DEG C; the heated feed liquor is filtered and then is fed into a membrane component to perform vacuum distillation and concentration; the flow rate of the feed liquor is 0.1-0.4m<3>/h and the degree of vacuum is 0.88-0.1MPa; the concentration of sodium chloride in the concentrated feed liquor reaches 280-290g/L, the reflux of the feed liquor is stopped, and the concentrated feed liquor enters a crystallizer to crystallize to separate salt; the crystallization temperature is 12-18 DEG C and the constant-temperature crystallization is performed for 60-120 minutes; and then standing is performed for 60 minutes at normal temperature. Crystallized and stood feed liquor is subjected to solid-liquid separation; and coarse salt is washed through sodium chloride solution and is dried at the temperature of 140-150 DEG C to obtain a refined salt product. The method has the advantages of energy conservation, small floor area and the like and has broad application prospect.