Construction and Demolition ( C&D ) waste constitutes a major portion of total solid waste production in the world. The main purpose of this research is to study the effect of addition of waste Yellow Clay brick powder (CBP) on the behavior of cement mortar and concrete of Grade (C25) at both conditions; fresh and hardened on the mechanical properties of concrete through by using of different partial replacement of powdered brick with cement until 100 percent by weight (0% , 5% , 10% , 15% , 20% , 25% , 50% and 100% ) to produce concrete and to reduce the impact on environment by consuming the material generally considered as waste product. The yellow clay brick was crushed and grinded manually and also sieve through 75µm sieve size in order to be fineness as cement. Cubes of size 150mm x 150mm x 150mm, Cylinders of size 300mm x 150mm and prisms of size 100mm x 100mm x 500mm were casted and tested, different ratios of waste CBP have been used to study its effect on the workability (slump flow), compressive strength and splitting tensile strength for 7, 14 and 28 days; and the modulus of rupture for 28 days. The results compared with the reference specimens and study the relationship between the mechanical properties of concrete.