Abstract: An ANSYS Workbench-based modal analysis is made on the stability of the underground sizing crusher's split-type frame assembly, and through which the distribution of vibration mode, as well as the principal vibration mode of the crusher frame are made known according to the inherent vibration frequencies and vibration patterns of different modal orders. And finally, an assessment is made on the design of the split-type crusher frame. As evidenced through analysis, the dynamic characteristics of the crusher frame manifest mainly in the form of wobbling and twisting motion, and no significant effect of the inherent frequency of the frame on the vibration of the frame's segmented points can be observed.