Abstarct: Nowadays, the use of recycled concrete for economic and environmental reasons has increased significantly and increasing the replacement of recycled aggregates change the properties of mechanical behavior of concrete. In this study, the mechanical behavior of concrete containing recycled aggregates with different percentages of steel and polypropylene fibers have been investigated in the laboratory. overall 36 cylindrical compression specimens, 36 cylindrical tensile specimens with dimensions of 200* 100 mm and 36 flexural specimens with dimensions of 100 * 100 * 350 mm were tested. Recycled aggregates (coarse aggregates) in ratios of 0, 25 and 50% (weight ratio) replaced natural materials. Also, steel and polypropylene fibers were added to recycled concrete specimens in ratios of 0%, 0.5%, 1% and 0%, 0.4%, respectively. Fiber reinforced concrete specimens containing recycled aggregates under compressive load, indirect tension and three-point bending are tested and factors such as compressive strength, splitting tensile strength, modulus of elasticity, flexural strength and fracture energy are investigated. The results show that compressive strength decreases with the content increase of recycled aggregate. Polypropylene fibers have a positive effect on increasing compressive strength and combination of polypropylene fibers with 0.5 and 1% steel fibers increases energy absorption by 68 and 169 times. Also, the maximum splitting tensile strength decreases with the content increase of recycled aggregate. The results of flexural strength test show that polypropylene fibers have a positive effect on increasing pick loads and preventing the collapse of concrete, and combination of these fibers with steel fibers increases the fracture energy, thus increasing the ductility.