The leading edge erosion of fan rotor blade will occur due to erosion wear and other effects during operation. A titanium alloy fan blade of a high bypass ratio engine is used as the research object to study the influence of leading edge erosion on aerodynamic characteristics and re-modeling design, and focuses on the analysis of working characteristic curve and flow characteristics in the tip area. The effect of erosion on the leading edge was simulated by blunt treatment of the blade’s leading edge. The FINE/Design 3D module in NUMECA software was used to study the optimization Design of the erosion leading edge re-modeling. The numerical results show that the leading edge erosion will lead to the overall downward movement of the flow-pressure ratio and flow-isentropic efficiency of the fan rotor blade 0.86% and 0.53%, the decrease of the stability working margin, and the forward movement of the blade tip shock structure. After the leading edge re-modeling, the aerodynamic performance of the fan rotor blade is restored to the original level.