Indigo dye is one of the dyes that has been used since ancient times and has maintained its importance to this day. Currently, indigo is obtained
synthetically and from natural sources. Synthesis of indigo uses non-renewable resources, hurting the environment. This encourages research to improve the efficiency of natural methods that do not harm the environment. We studied the effect of ultrasound on the extraction of leaves of Indigofera tinctoria L and the acceleration of the fermentation process. The conducted studies showed that under the influence of ultrasound, the fermentation process time was shortened, and indigo dye was expected to be produced more efficiently.