Abstract: The honeycomb core of cells was modeled as a layer of orthotropic material whose physical and the mechanical properties were determined by the corrected Gibson’s formula.Based on the classical plate theory, a preliminary study was conducted for the natural frequency of the honeycomb sandwich plate with completed clamped supported. The effects of panel thickness and core thickness on the natural frequency of honeycomb were investigated. Furthermore, the finite element simulations with equivalent parameters performed. The results show that the method can exactly calculate the natural frequency of honeycomb.