To provide a method for purifying pyroligneous acid and an apparatus therefor, designed to uniformize the heating of a stock liquor in a distillation tank, leading to improving heating efficiency, facilitate extracting tar fraction, prevent the purified pyroligneous acid from discoloration, and accomplish labor saving for the apparatus as a whole.

First, a stock liquor M as a whole is heated by a heating means 12 while agitating the stock liquor M from its uppermost part through the lowermost part by the blades 133 of an agitating means 13. Secondly, the purified gas evaporated is condensed by a condenser 2 and the resultant purified pyroligneous acid is put into a holding vessel 3 and charcoal 31 is immersed therein to prevent the purified pyroligneous acid from discoloration. Thirdly, a level gauge 14 is visually observed to extract the tar fraction in the distillation tank by opening an on-off valve 15a. Feed of the stock liquor may be continuously performed through a stock liquor feed pipe 11 by connecting the purification system to a carbonizing apparatus 4 and condensing the resultant flue gas; in this case, steam raised in temperature by making use of the heat of the flue gas may be fed via a circulating piping 8 into the distillation tank 1 and the stock liquor M heated by making use of the heat of the steam.