To provide a method for producing metallic soap, capable of obtaining metallic soap having good color and excellent in quality, capable of readily carrying out wastewater treatment, scarcely having wastewater amount and not causing environmental pollution by effectively utilizing deacidified waste fluid produced by purification step of pressed oil and fat.

Nondeacidified oil and fat is subjected to deacidification treatment by using an aqueous solution of hydroxide to separate deacidified oil and fat and provide a deacidified wastewater consisting essentially of glyceride and fatty acid sodium salt. Aqueous solution of sodium hydroxide is added to the deacidified wastewater to saponify glyceride in the acidified waste liquid and an aqueous solution of metal salt is added thereto and metallic soap is produced by double decomposition.