The fiber used in concrete is widely used since it can enhance strength and elastic properties. In this research, steel fibers were used in three different percentages in three groups (A, B, and C) (0%, 0.5%, and 1.5 %) to investigate the load-displacement value for the beams are on mat foundation. The experimental program consists of two beams and three cubes for each percentage of steel fiber. The results showed that beams that contained 0% of steel fiber were referred as to control specimens. Two spacings of stirrups were investigated in beams: 50 mm and 100 mm. The objective of this study is to investigate the optimum percentage of steel fibers in SFRC on a mat foundation and to study the maximum load capacity of SFRC beams compared with conventional reinforced concrete beams on mat foundation. A1 (50 mm spacing) failed at 178 kN with 4.5 mm displacement, while the highest load was 182 kN with 4.5 mm displacement in an A2 (100 mm spacing) specimen. The analytical beam with no steel fiber shows a failure load at 181 kN with 4 mm displacement. Specimens that have 0.5% of steel fiber in B1 (50 mm spacing) and B2 (100 mm spacing) have almost the same failure load. The average failure load was 229 kN with an average displacement of 6.4 mm. The analytical beam with 0.5% steel fiber shows a failure load of 217 kN with 5.5 mm displacement. Specimens that have 1.5% steel fiber C1 (50 mm spacing) failed at 195 kN with 6.1 mm displacement, while C2 (100 mm spacing) has a failure load of 198 kN with 5.9 mm displacement. The analytical beam with 1.5% of steel fiber shows a failure load of 192 kN with 4.7 mm displacement. In ABAQUS, the simulation of specimens has the same trend as experimental specimens. The specimens that have 0.5% of steel fiber have the most significant load, while the specimens with 0% of steel fiber have the lowest load. The effect of steel fiber dosage was apparent in the B and C groups. The C group with 1.5 percent of steel fiber has a smaller failure load than 0.5 percent (B group); this is attributed to the replacement of steel fiber to take the place, of course, aggregate