Through the pull-out test of steel fiber and cement matrix, obtained the force-displacement curves of different angles, and then the random and aligned steel fiber reinforced cementitious composites (SFRC, ASFRC) meso finite element numerical model were established. The whole fracture process of SFRC and ASFRC three-point bending beams with different fibers content is calculated, and the meso-scale numerical model is verified by the fracture test, the meso-reinforcement mechanism of aligned steel fiber is studied. The research show that, the peak pull-out force first increases and then decreases with the fiber inclination angle; the peak loads of the SFRC specimens and ASFRC specimens both increase with the increase of the fibers content, when the fibers content is 0.8%, 1.2% and 2.0%, the peak load of the ASFRC specimens is about 80%, 105% and 114% higher than that of the SFRC specimens; the whole load-crack opening displacement (P-CMOD) curves of test and numerical simulation have a good suitable, which obtained from the SFRC specimens and the ASFRC specimens, and the error of the peak load is within 10%; under the same fibers content, the maximum fibers force of the ASFRC specimens is greatly improved compared with the SFRC specimens, indicating that the utilization rate can be significantly improved after the steel fibers are aligned, delay the generation and expansion of cracks.