Dihydroxyacetone is a triose carbohydrate with the chemical formula C₃H₆O₃. It is the simplest of all ketoses and, having no chiral centre, is the only one that has no optical activity.

It may be prepared, along with glyceraldehyde, by the mild oxidation of glycerol, for example with hydrogen peroxide and a ferrous salt as catalyst.

Dihydroxyacetone is used in the cosmetics industry as a tanning substance.