Reinforced concrete has been widely used. However, it is difficult to accurately simulate the process of concrete damage and destruction caused by rebar corrosion. Therefore, the objective of this work is to solve this difficult problem using a phase field method and analyze the failure process of reinforced concrete. The main importance of this work is to improve the calculation method for the problem, simulate the damage and destruction of concrete cover, and visualize the crack propagation process. Based on the strain softening characteristics of concrete the damage of concrete cover caused by uniform and non-uniform corrosion of rebars is simulated respectively. The simulation results are consistent with the actual observation. The applicability of the phase field method for complex crack propagation in reinforced concrete is verified, which provides a reference for the engineering design and durability research of structures. Analysis of simulation results found that the crack propagation speed is fast for uniform corrosion. Increasing the thickness of concrete cover is benefit to improve the corrosion resistance of structure. However, the crack propagation speed is slow for non-uniform corrosion. The thickness of the cover has no obvious effect on the corrosion damage resistance of structure. For the non-uniform corrosion of multiple rebars, depending on the thickness of concrete cover and the spacing between rebars, the concrete cover presents three typical crack propagation morphologies: wedge-shaped cracks, layered cracks and small local cracks.