The effect of layer height on the inherent characteristics of FDM (fused deposition modeling) plates is studied, and the mechanism is revealed. First, the theoretical model of the inherent characteristics of the FDM plates under cantilever boundary conditions is established and the corresponding samples are designed. Then, the dynamic testing system for the sample is set up, and the inherent characteristics of the sample are measured. Finally, the predicted and measured results are compared to validate the theoretical model. The results show that the theoretical model can reliably predict the dynamic inherent characteristics of FDM plate structures. The larger the layer height is, the higher the natural frequency of the sample will be. But the mode shape will not change with the layer height. The study provides a theoretical basis and technical support for further research on improving the dynamic performance of FDM products.