Hydroxypivalaldehyde production method

A hydroxypivalaldehyde (HPA) production method, comprising steps (i) to (iii) as mentioned below in this order, wherein the distillation step (iii) is a step of carrying out distillation in the co-presence of an extract and water, and the amount of water to be subjected to the distillation is 100 to 2,000 parts by mass inclusive relative to the total amount, i.e., 100 parts by mass, of isobutylaldehyde (IBAL) derived from the raw material in the extract to be subjected to the distillation and an aldehyde solvent represented by formula (1). A production method can be provided, whereby it becomes possible to produce HPA in a large amount and it also becomes possible to improve the rate of collection of HPA while selectively removing non-water impurities, particularly IBAL and the like, contained in HPA. According to the above-mentioned HPA production method, it also becomes possible to reduce the contents of specific impurities that are produced secondarily as by-products from HPA, i.e., neopentyl glycol-isobutyric acid ester, isobutylaldehyde-hydroxypivalaldehyde-acetal and isobutylaldehyde-hydroxypivalaldehyde-aldol. Step (i): a reaction step of reacting IBAL with FA to produce a reaction solution containing HPA, step (ii): an extraction step of extracting the reaction solution with an aldehyde solvent represented by formula (1) under basic conditions to produce an extract containing HPA, and step (iii): a distillation/collection step of distilling the extract and then collecting HPA from the residue. (In formula (1), R represents a saturated alkyl group having 3 to 7 carbon atoms inclusive.)