The invention relates to a process for producing monopentaerythritol of high purity and monopentaerythritol produced by the process. Formaldehyde is reacted with acetaldehyde in an aqueous solution in the presence of a strongly basic hydroxide in a conventional way. The obtained reaction mixture is evaporated to a dryness of 50-70% by weight and is thereafter cooled. Crystals of pentaerythritol thereby formed are separated off. The crystals are dissolved in water or in a water-containing mother liquor containing pentaerythritol to a dryness of 35-55% by weight. The solution is treated in a purification step whereupon monopentaerythritol of high purity is crystallized at a temperature of 40-90.degree. C. and separated from the remaining mother liquor which is recirculated to the above mentioned step.