The invention relates to an eleven-effect combined sodium and potassium preparation device. A ten-thousand-ton four-effect vacuum evaporation sodium chloride preparation device, a ten-thousand-ton four-effect vacuum evaporation sodium chloride further preparation device and a three-effect potassium chloride device are connected in series. After passing through the first ten-thousand-ton four-effect vacuum evaporation sodium chloride preparation device, the raw material of brine enters a V-effect evaporation tank for second ten-thousand-ton vacuum evaporation and finally is transferred into an XI-effect evaporation chamber tank for three-effect potassium chloride preparation. According to the eleven-effect combined sodium and potassium preparation device, mother liquor discharged out of a first ten-thousand-ton salt production workshop can be directly used as a raw material in a second ten-thousand-ton salt production workshop, the temperature of the mother liquor is higher than that of a raw material which is directly dried in the sun and fed, and therefore steam consumption is lower than that of single four-effect vacuum evaporation salt preparation; in this way, energy of the mother liquor can be recycled, steam consumption is greatly reduced, and meanwhile a heat exchanger in the second ten-thousand-ton salt production workshop can be omitted; since the mother liquor directly enters a second evaporation tank, the area of a salt pond for solar evaporation is saved.