This paper was studied by using a series of containing hydroxyl and carboxyl group monoazo dyes. All dyes were dyed on polyester/wool blend fabric at different pH-value (pH=3,4,5,6) which were also evaluated the colour strength dye uptake and fastness properties. lt might be concluded that, the fastness of all the dyed samples were in accord with commercial require mean and Dye3C, DyelD, were suitable for polyester/wool blend fabrics.