Recently, the exploration of two-dimensional (2D) ferromagnetic materials has become a hot topic in the field of spintronic devices. In this work, Fe3As, a new two-dimensional material, with Curie temperature (Tc) of 300 K (reach room temperature), was designed by means of spin-polarized density generalization theory calculations. The predicted 2D Fe3As has strong in-plane Fe—Fe coupling with large magnetic anisotropy energy (MAE) of approximately 366.7 μeV, which contributes to maintain a long-range ferromagnetic order. The energy band of Fe3As has both flat band and Dirac point features. The position of the flat band is positively related to the strength of the magnetic coupling. Furthermore, Tc increases progressively as the distance between the flat band and the Fermi surface continues to decrease under the effect of the biaxial strain. Therefore, Fe3As monolayer is considered to be a promising candidate for 2D room-temperature spintronics devices.