Occurrence, properties and applications of laďic acid (E 270) in this article were described. Lactic acid is produced on an industrial scale in result of fermentation of carbohydrates by the use of various bacteria. In food industry lactic acid acts as pH control agent and antioxidant. Moreover, lactic acid on wide scale in pharmaceutical and cosmetic industry is used, somewhat smaller use he has found in agriculture as well as in textile and dyeing industry.