The steering wheel of a grain combine harvester was used to establish the geometric model of the steering wheel based on Pro/E software. The modal of the steering wheel combination model were analyzed by using finite element analysis software (ANSYS). The results showed that the first natural frequency of the model was 44.005 Hz,close to the range of human hand sensitive vibration frequency from 37.5 Hz to 65.0 Hz,and affected the health of operators. In order to adjust the natural frequencies of the assembly model to avoid the sensitive frequencies of human hands,the structure of the assembly was optimized by increasing the diameter of steering column and transmission shaft on the basis of replacing the material of steering wheel frame with 45 steel. After optimization,the first natural frequency of the combined body model is increased from 44.005 Hz to 67.31 Hz,avoiding the hand-sensitive vibration frequency and engine excitation frequency. The model optimized can avoid the resonance phenomenon and improve the operational comfort of operators.