Weathering resistant steel with high Mo content and preparation method thereof

The invention discloses weathering resistant steel with high Mo content and a preparation method of the weathering resistant steel, and the weathering resistant steel comprises the following components in percentage by mass: 0.20 to 0.55 percent of Mo, 0.2 to 0.5 percent of Si, 0.4 to 0.6 percent of Cu, 0.005 to 0.02 percent of P, 0.5 to 1.3 percent of Cr, 0.3 to 0.75 percent of Ni, 0.2 to 0.3 percent of Ti and the balance of Fe. In the hot rolling process, grain refinement is obvious, a ferritic structure or a ferritic and pearlitic structure is achieved, the mechanical property and corrosion resistance are excellent, the preparation method is simple, after hot rolling is completed, follow-up treatment such as annealing is not needed, the method is simple and easy to implement, and test results show that the carbide precipitation strengthening effect is 350-460 MPa, the yield strength is 860-975 MPa, and the yield strength is 860-975 MPa. And the percentage elongation after fracture is 19.5 to 23.4 percent.