The subject of the invention relates to a method for the economical production of deuterium depleted water - DDW. The invention' s distinctive feature is that hydrocarbons of mineral origin are oxidised, the water created as a product of this is condensed, and in this way water with an average deuterium content lower than the natural deuterium content of 122- 126 ppm is produced, which is lower than the natural deuterium content of 155 ppm, then preferably it is subjected to fractional distillation for the purpose of further deuterium depletion.