A method for purifying a crude (meth)acrylic acid obtained by a vapor
phase catalytic oxidation method, characterized in that the crude
(meth)acrylic acid having most parts of water and acetic acid removed
therefrom, is fed to and distilled in a first distillation column of a
purification system comprising first to third three distillation columns,
the top fraction from the first distillation column is fed to and
distilled in the second distillation column, the resulting top fraction
is recovered as a high purity (meth)acrylic acid product, the bottoms
from the first and second distillation columns are fed to and distilled
in the third distillation column, and the resulting top fraction is fed
to the first distillation column.