Para-Aramid fibers are very tough and strong polymer materials. They are widely used for the manufacture of high-performance industrial textiles. In this study, we examined the effects of different concentrations of aramid staple fibers on the mechanical properties of wool/PET/aramid blended spun yarn and fabric. Three different fiber compositions were used to produce aramid fabrics with aramid fiber contents of 0-10%. We measured the mechanical properties of these aramid blended fabrics: the tensile strength, wear strength, and fastness against washing, friction, and daylight. The tensile test results demonstrated that the mechanical properties of the aramid blended fabric change with the amount of aramid staple fibers. In particular, 6% aramid blended fabrics showed the best physical properties, but higher aramid concentrations produced no further changes. One reason could be the decrease in mechanical properties due to the low cohesion stress of individual aramid fibers. In conclusion, a woven fabric made of 3-6% aramid staple fibers blended with spun yarn can increase the mechanical properties of apparel.