Wool, compared to other natural materials, has the ability to reduce the development of unpleasant odors on clothing. It is believed that the structure of wool fibers does not favor the development of bacteria, and lanolin on the surface of the fiber protects the sheep from infections. The aim of this study was to evaluate the antibacterial properties of wool using agar diffusion test (ISO 20645: 2004) and to suggest a mechanism of action by determining the number of bound bacteria on wool after 1 and 24 hours of contact with bacteria on nutrient media. Wool was compared to cotton and medical gauze. Tested bacteria were S. aureus, K. pneumoniae, B. cereus, and several strains of A. baumanni, including two hospital isolates. According to the agar diffusion test, wool showed a good antibacterial effect (determined by the absence of bacteria on the nutrient medium below the textile sample) for all bacteria except S. aureus. Cotton showed insufficient to good antibacterial effect for tested bacteria. Medical gauze showed marginal and insufficient effect for all tested bacteria. For most of the bacteria tested, there is no significant difference in the number of bound bacteria between wool, cotton and gauze after 1 hour of contact. After 24 hours of contact for most bacteria, wool showed less or equal number of bound bacteria compared to gauze, and greater or equal to relative to cotton. The surface of the wool allows very good adhesion of bacteria, but bacteria continue to multiply significantly on it. The antibacterial effect is therefore the result of a strong binding of bacteria to the wool fiber, thus reducing the presence of bacteria on the nutrient media under the wool sample.