According to the resonant pavement crusher's work principle, its front frame mounted with the resonance system must meet the needs of the structural requirements. To satisfy the strength and stiffness requirement and avoid the resonance, the natural frequency of the front frame should be designed away from the crusher's working frequency. In this paper, the author builds a finite element model of the front frame and analyses its modal. According to the modal analysis results, the fourth modal frequency is close to the working frequency of the crusher. So the front frame should be optimized. In the finite element model, the front frame has been divided into a number of components of shell elements. Through optimal Latin hypercube experimental design, the author analyses the different component thickness's relationship of the frequencies of the front frame. The components with higher correlation coefficient have been chosen as the variables of optimization. The sample points for optimization are obtained by the Design of Experiment (DOE) with optimal Latin hypercube. The approximation models of mass and frequency are established with the polynomial Response Surface Method (RSM). The thicknesses of chosen components are selected to be optimized by adaptive response surface method. After the optimization of the front frame, the first frequency increases, so does the 4th frequency.