Experimental tests were carried out to study the effect of using combining steel and polypropylene fibers on cracking resistance of R.C. elements under both static and dynamic loading. The tested R.C. elements were containing of steel, polypropylene and combination of both steel and polypropylene fibers, using dosages as 1.0 %, (by volume).The tested R.C. elements were reinforced with constant amount of steel bars and constant cross-section. They tested under four point both static and dynamic loading. The mid-span deflections, crack width, number of cracks, first crack load, and ultimate load capacity were recorded as well as cracks propagation were observed. The experimental results show that the R.C. elements containing of combining steel and polypropylene fibers are enhanced improvements in the cracking resistance and their characteristics as will as their serviceability when compared with using individual fibers.