PURPOSE: To efficiently, industrially and advantageously obtain the titled compound useful as a synthetic raw material for medicines agricultural chemicals, etc., in good yield, by reacting monochloroacetone with Cl2 at a specific temperature using a specific solvent.

CONSTITUTION: A reactor having a condenser is charged with monochloroacetone and an organic solvent, preferably a 1W3C saturated halogenated hydrocarbon, such as methylene chloride or isopropyl chloride, having ≤40°C boiling point and inert to Cl2 and HCl. Cl2 is continuously charged while keeping the mixture at 40W70°C and reacted therewith. Distillation is then carried out to separate the added organic solvent and high-boiling components, such as 1,3- dichloroacetone, 1,1,3-trichloroacetone of 1,1,1-trichloroacetone, and afford the aimed high-purity compound. The above-mentioned organic solvent may be present in an amount of normally ≥25% based on the reaction solution.