To sterilize harmful bacteria such as pathogenic Escherichia coil or Salmonella, which stick to the meat or fish by allowing meat or fish to contact with strongly acidic water formed with electrolysis of water and utilizing the sterilizing action due to a synergistic effect of active chlorine and active oxygen in the acidic water.

In this method, meat such as beef, pork, mutton, chicken or horseflesh, or fish such as fish of a tuna, swordfish, bonito, saurel, porgy, flounder or flatfish is allowed to contact with a strongly acidic water formed with electrolysis of water. At this time, preferably, sodium chloride is added to feed water used for the electrolysis to set the specific electrical conductivity of the feed water to ≤200μms/cm2.