Abstract: This invention is linked to the chemical, pharmaceutical and cosmetic industries, where the bactericidal, virucidal, parasiticidal and fungicidal properties of the ozonized vegetable oils and fats are considered. The emulsified vegetable oil or fat is driven to react with ozone in a bubbling reactor, covered by a jacket that makes possible to control the reaction's temperature. Ozone reacts with the double bonds present in vegetable oil or fat, giving rise to the formation of different peroxidic species, responsible for the biological action of those products. The ozonized vegetable oils and fats in those conditions are applied with satisfactory and advanced results to the treatment of diseases in diverse medical specialties, such as ophthalmology, dentistry, dermatology, gastroenterology, gynecology, parasitology, and others. Likewise, the cosmetic application of the ozonized vegetable oil and fats is described, considering their oxygenating and revitalizing properties of the skin.