A new kind of material cast polyurethane elastomers (CPUE) is introduced to take the place of rubber on load-bearing wheel for the first time. Based on load-bearing wheel dimensions, material properties and operating conditions, the structure of wheel flange is optimized by zero-order finite element method. A detailed three-dimensional finite element model of flange of load-bearing wheel is developed and utilized to optimize structure of wheel flange. Its service life, which is affected by flange structure parameter, is analyzed by comparing the optimization results with those of prototype of wheel. The results of optimization are presented and the stress field of load-bearing wheel in optimal dimension obtained by using finite element analysis method is demonstrated. The finite element analysis and optimization results show that the CPUE load-bearing wheel is feasible and suitable for the tracked vehicle and has a guiding value in practice of the weighting design of the whole tracked vehicle.