The growing need for sustainable textile recycling methods has promoted research into enzymatic treatments as an environmentally friendly alternative to recycle fiber blends, in particular those composed of viscose and cellulose with other synthetic fibers such as polyester or polyamide. Traditional recycling methods face difficulties in separating natural fibers from synthetic fibers, leading to degradation of fiber quality or limiting their reuse. Enzymatic processes, however, offer selective degradation of natural fibers while preserving the integrity of synthetic components, allowing for more efficient recycling and blended textiles. This study investigates the use of specific enzymes, such as cellulases, to selectively degrade cellulose-based fibers (viscose and cotton) in blended fiber fabrics, facilitating the separation of synthetic fibers. The enzymatic treatment not only allows for the recovery of synthetic fibers, but also produces a controlled decomposition of natural fibers, which can be reused or reintegrated into new textile products. In addition, the process reduces the need for polluting chemicals and minimizes water and energy consumption, in line with the principles of the circular economy in the textile industry. Furthermore, the enzymatic activity of the cellulase used is analyzed according to the type and percentage of each fiber in the treated fabric. The results show that the enzymatic treatments effectively degrade the natural fiber components without affecting the synthetic fibers, allowing them to be reused. As well as, the enzymatic activity is influenced by the type of cellulosic fibre to be degraded and the percentage in which it is found in the fabric.