The orientation of steel fibers has an effect on the mechanical properties of steel fiber reinforced concrete (SFRC). In elements or structures such as slabs, floors and pavements, vertical steel fibers are useless but harmful to the structures. In this case, the optimal distribution of steel fibers is two-dimensional (no vertical, but random in the plane) dispersion. In this paper, the steel fibers were aligned using a rotating uniform magnetic field, and the 2D aligned steel fiber reinforced concrete (2D-SFRC) was prepared to enhance the mechanical properties of SFRC and the efficiency of reinforcement of steel fibers. The splitting tensile performance, flexural behavior of prism and circular plate specimens of 2D-SFRC were tested and compared with those of the specimens with randomly distributed steel fiber reinforced concrete (RD-SFRC). Besides, the mechanism of reinforcement of 2D-SFRC was investigated from the perspective of fiber distribution characteristics and acoustic emission signals. The results show that the mechanical properties of 2D-SFRC are significantly improved, compared with RD-SFRC. The fiber distribution statistics and acoustic emission analysis indicate that the increased amount of steel fibers in the fracture surface and enhanced fiber orientation effective factor are the main reasons for the improved mechanical properties of 2D-SFRC. The 2D-SFRC has the characteristics of high performance and low cost, which is of great significance for improving the engineering quality and reduce the materials consumption.