In this research an experimental study was carried out to investigate the effect of adding marble and porcelain waste as replacement of sand by certain percentages on mechanical properties of concrete containing (100%) recycled coarse aggregate and compare its properties with concrete mixture containing natural coarse and fine aggregate. Four mixes were prepared the first one is the control mix having natural coarse and fine aggregate, second mix containing (100%) recycled aggregate and natural fine aggregate, third mix containing (100%) recycled aggregate and (5%) marble waste as replacement of sand and last mix containing recycled aggregate(100%) and (10%) porcelain waste as replacement of sand.The ratios of Added Materials (marble, porcelain waste) depended on the results obtained from tested cement mortar cubes having different proportions of the two materials, the selected ratios were the ones giving the highest compression strength. The results of tests showed that using of recycled coarse aggregate as alternative to natural coarse aggregate gives good quality concrete and a compressive strength higher than the compressive strength of original concrete by (5.1%) and it helps increasing modulus of rupture by (19.5%) compared to the original concrete. The results show that using recycle aggregate lead to reducing tensile strength by (35%) compared to the original concrete. Using of marble waste as replacement of sand lead to significant increase in compressive strength by (5.1%), while using porcelain waste gives same compressive strength of reference mix. Using marble and porcelain waste lead to significant increase in tensile strength reach to (35%) and (17.6%) respectively. The results show there is an increase in modulus of rupture when using marble and porcelain waste reach to(24%) and (19.5%) respectively, but it reduced workability of concrete mixtures.