For solving issues of the wave performance applicability of the deformation-based equivalent model for Honeycomb Sandwich Panels (HSPs) and difficulty in sensing signal feature extraction for debonded delamination identification, an equivalent conversion method is used by changing an HSP structure into a three-layered periodic structure, and the Comsol Multiphysics software is applied to calculate and draw frequency dispersion curves. The guided wave performance applicability is investigated by comparing two kinds of finite element (FE) analysis results from the equivalent and actual two models of the HSP structure. The FE method is applied to explore the feature of guided wave deboned-induced-split-flow. The model tests are used to validate the correctness of the frequency dispersion performance and the deboned-induced-split-flow feature of high-frequency guided waves. The results show that the wave performance differences between the equivalent conversion and actual models are obvious as the wavelength of guided wave is not greater than a single cell height in the HSP, the debonded delamination is the main reason for deboned-induced-split-flowing, and it is recommended that the time-domain sensing signals of high-frequency activated A0 mode guided waves are used as extracted features for the debonded delamination identification of HSP structures.