PURPOSE: To purify glycidol by distilling off almost all of low-boiling components from a crude solution containing glycidol, then adding trioctylamine to the residue to remove carboxylic acids with the acidic content reduced.

CONSTITUTION: From the crude reaction mixture obtained by reaction of allyl alcohol with peracetic acid, carboxylic acids as by-products such as acetic acid, propionic acid and the like are removed. The removal is carried out by distillation. After almost all of low-boiling fractions are distilled off, trioctylamine of low basicity is added to effect neutralization, the mixture is separated into two phases. Trioctylamine is added in an amount of 1-10 time moles of the acidic components to effect the neutralization at 0-30°C. The glycidol is useful as an synthetic intermediate for glycidy ethers, glycidyl esters, glycerol ethers, propane diol, medicines, agrochemicals, coatings, UV curing agents for semiconductor.