In this study, Peanutred skin (Arachis hypogaea L.) colorant extract was applied on wool fabric using alum (aluminum potassium sulfate) andferrous sulfate as mordant. The effect of treatment variables such as dye concentration, pH of dyeing bath, timeand temperature of dyeingprocess on the color strength and colorimetric data of dyed fabrics was examined. The fastness properties of dyed wool against rubbing , washing and light were evaluated. The use of metal mordants increased the color strength of the dyed fabrics. All mordants improved the fastness properties of the dyed fabrics toward perspiration, rubbing, washing, and light. Peanut red skin extractis a cationic dye Exhibits antimicrobial activity by virtue of its quaternary ammonium structure. So, dyed samples were tested for antibacterial activity using AATCC test method 100-2004. The dyed wool represented a high level of antibacterial activity. The extract of the Peanut red skin can be considered as a natural dye of acceptable fastness properties together with excellent antibacterial activity for woolen fabrics.